Two chemicals A and B are combined to form a chemical C. The rate, or velocity, of the reaction is proportional to the product of the instantaneous amounts of A and B not converted to chemical C. Initially, there are 40 grams of A and 50 grams of B, and for each gram of B, 2 grams of A is used. It is observed that 20 grams of C is formed in 10 minutes. How much (in grams) is formed in 20 minutes? (Round your answer to one decimal place.)

Answers

Answer 1

Answer:

  32.1 g

Step-by-step explanation:

In each 3 grams of C, there are 2 grams of A and 1 gram of B. So, for some amount C, the amount remaining of A is 40 -(2C/3), and the amount remaining of B is (50 -C/3). Since the reaction rate is proportional to the product of these amounts, we have ...

  C' = k(40 -2C/3)(50 -C/3) = (2k/9)(60 -C)(150 -C) . . . for some constant k

This is separable differential equation with a solution of the form ...

  ln((150 -C)/(60 -C)) = at + b

We know that C(0) = 0, so b=ln(150/60) = ln(2.5). And we know that C(10) = 20, so ln(130/40) = 10a +ln(2.5) ⇒ a = ln(1.3)/10

Then our equation for C is ...

  ln((150 -C)/(60 -C)) = t·ln(1.3)/10 +ln(2.5)

__

For t=20, this is ...

  ln((150 -C)/(60 -C)) = 2ln(1.3) +ln(2.5) = ln(2.5·1.3²) = ln(4.225)

Taking antilogs, we have ...

  (150 -C)/(60 -C) = 4.225

  1 +90/(60 -C) = 4.225

  C = 60 -90/3.225 ≈ 32.093 . . . . . grams of product in 20 minutes

In 20 minutes, about 32.1 grams of C are formed.


Related Questions

The organization that Jones works for is running for a father son dinner for those employees is invited to attend along with his youngest son. If Jones is known to have two children, what is the condition probability that they are both boys given that he is invited to the dinner?

Answers

Answer:

25%

Step-by-step explanation:

The probability of having a boy is 50%

To calculate the probability of him having 2 boys, multiply the probabilities together

0.5(0.5) = 0.25

The graph of y = 1/2 x2 + 2x + 3 is shown. What are the solutions to the equation 1/2 x2 + 2x + 3 = x + 7?

Answers

Answer:

Step-by-step explanation:

Let's organise our information :

the function is (1/2)x²+2x+3

we want to khow the value of x that gives us : (1/2)x²+2x+3=x+7

Now the trick is to write this expression as a quadratic equation with zero at one side :

(1/2)x²+2x+3=x+7 (1/2)x²+2x+3-x-7=0(1/2)x²+x-4=0

Now let's solve this equation :

a= 1/2b= 1c= -4

Δ=1²-4*(1/2)*(-4)

 = 9

So we have two solutions :

[tex]\left \{ {{y=\frac{-1-3}{2*0.5} } \atop {x=\frac{-1+3}{2*0.5} }} \right.[/tex]y= -4x= 2

So the solutions are -4 and 2

T or F? Is 3y=5x If x is 3 and y is 5?

Answers

Answer:

True

Step-by-step explanation:

3y=5x

Put x as 3 and y as 5.

3(5) = 5(3)

15 = 15

Hence, true.

Answer:

true

X=3

y=15

[tex]3y = 5x \\ 3 \times 5 = 5 \times 3 \\ 15 = 15[/tex]

Proved.

Hope it helps..

Kurtis is a statistician who claims that the average salary of an employee in the city of Yarmouth is no more than $55,000 per year. Gina, his colleague, believes this to be incorrect, so she randomly selects 61 employees who work in Yarmouth and records their annual salaries. Gina calculates the sample mean income to be $56,500 per year with a sample standard deviation of 3,750. Using the alternative hypothesis Ha:μ>55,000, find the test statistic t and the p-value for the appropriate hypothesis test. Round the test statistic to two decimal places and the p-value to three decimal places.

Degrees of Freedom

0.0004 0.0014 0.0024 0.0034 0.0044 0.0054 0.0064
54 3.562 3.135 2.943 2.816 2.719 2.641 2.576
55 3.558 3.132 2.941 2.814 2.717 2.640 2.574
56 3.554 3.130 2.939 2.812 2.716 2.638 2.572
57 3.550 3.127 2.937 2.810 2.714 2.636 2.571
58 3.547 3.125 2.935 2.808 2.712 2.635 2.569
59 3.544 3.122 2.933 2.806 2.711 2.633 2.568
60 3.540 3.120 2.931 2.805 2.709 2.632 2.567

Answers

Answer:

Test statistic t = 3.12

P-value = 0.001

As the P-value (0.001) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the average salary of an employee in the city of Yarmouth is is significantly greater than $55,000 per year.

Step-by-step explanation:

This is a hypothesis test for the population mean.

The claim is that the average salary of an employee in the city of Yarmouth is is significantly greater than $55,000 per year (Gina's claim).

Then, the null and alternative hypothesis are:

[tex]H_0: \mu=55000\\\\H_a:\mu> 55000[/tex]

The significance level is 0.05.

The sample has a size n=61.

The sample mean is M=56500.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=3750.

The estimated standard error of the mean is computed using the formula:

[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{3750}{\sqrt{61}}=480.138[/tex]

Then, we can calculate the t-statistic as:

[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{56500-55000}{480.138}=\dfrac{1500}{480.138}=3.12[/tex]

The degrees of freedom for this sample size are:

df=n-1=61-1=60

This test is a right-tailed test, with 60 degrees of freedom and t=3.12, so the P-value for this test is calculated as (using a t-table):

[tex]\text{P-value}=P(t>3.12)=0.001[/tex]

As the P-value (0.001) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the average salary of an employee in the city of Yarmouth is is significantly greater than $55,000 per year.

A department store chain is expanding into a new market, and is considering 13 different sites on which to locate 5 stores. Assuming that each site is equally likely to be chosen, in how many ways can the sites for the new stores be selected?

Answers

Answer:

Hope it helps you :)

And i hope you understand  

For store 1, it can be placed on 16 sites. Store 2 can be placed on 15 sites( since store 1 is already on site 1). Store 3 can be placed on 14 sites and so on until store 5 which has 12 sites.

Therefore the number of way is

C= 16*15*14*13*12

c=524,160 possibilities

In the morning, Marco sold 12 cups of lemonade for $3. By the end of the day, he had earned $9. How many cups of lemonade did he sell in all? Kaycee wrote the proportion 12/3=9/c for this situation identifly the error and give tow ways to write the proportion correctly

Answers

Answer:

36 cups

3/12 = 9/c

Step-by-step explanation

3 ÷ 12 = .25

each cup = 25 cents

9 ÷ .25 = 36

Marco sold 36 cups of lemonade.

3/12 = 9/c

Answer:

36 cups

Step-by-step explanation:

We can set up a proportion:

12/3=c/9

Cross multiply.

12*9=3*c

108=3c

Divide both sides by 3.

c=36

The error that the proportion Kaycee set up was

cups/price=price/cups

This is not proportionate.

Possible proportions include:

cups/price=cups/price

price/cups=price/cups

cups/cups=price/price

price/price=cups/cups

will give brainliest help plz i can't get back on the password won't go to my email and my little brother changed the password I am scared I lost everything PLZ HELP ME

Answers

What email do you use? If you have another email to secure it, you can use the “forgot password” site

simplify the expression into form a+bi, where rational numbers

(4-i)(-3+7i) - 7i(8+2i)

Answers

Answer:

-12+28i+3i-7i-65i+28

14 -41i

How many gallons of a 50% antifreeze solution must be mixed with 90 gallons of 10% antifreeze to get a mixture that is 40% antifreeze? Use the six step method.​

Answers

Answer:

x = 270 gallons

270 gallons of a 50% antifreeze solution must be mixed with 90 gallons of 10% antifreeze to get a mixture that is 40% antifreeze

Step-by-step explanation:

Let x represent the number of gallons of the 50% antifreeze solution.

The volume of the 10% antifreeze is = 90 gallons

The volume of the mixture that is 40% antifreeze = 90+x

The amount of antifreeze in the two solutions must be equal to the amount of anti freeze in the mixture;

50% of x + 10% of 90 = 40% of (90+x)

0.50(x) + 0.10(90) = 0.40(90+x)

0.50x + 9 = 36 + 0.40x

Collecting the like terms;

0.50x - 0.40x = 36-9

0.10x = 27

x = 27/0.10

x = 270 gallons

270 gallons of a 50% antifreeze solution must be mixed with 90 gallons of 10% antifreeze to get a mixture that is 40% antifreeze

Randomthing2143 help me please! Range of: 1, 2, 3, 1, 5, 2, 1, 8, 9, 7?

Answers

Answer:

8

solution,

Highest score=9

lowest score=1

now,

range= highest score-lowest score

=9-1

=8

Hope this helps...

Answer:

8

Step-by-step explanation:

The range of the sequence is the largest number - the smallest number.

The largest number is 9.

The smallest number is 1.

9 - 1

= 8

The range of the sequence is 8.

helppppppppp hurryyyyyyyyyyyyyyyyyyyyyyyy

Answers

Answer:

2

Step-by-step explanation:

I would have to say it is two bc Everitt had 30% where Desery had 20%.

ALGEBRA Identify the similar triangles. Then find each measure.
FG
S
G
6
х
R
4
T
F
10
H
ARST - AFGHFG = 11
ARST - AFGHFG = 14
ARST - AFGH FG = 15
ARST- AFGH FG = 18

Answers

Answer:

fg t f h 10

Step-by-step explanation:

4) →BRAINLIEST & 10+ POINTS! ← A wheel with diameter 44 cm completes four revolutions in 0.5 seconds. Find the linear speed of the edge of the wheel in cm per second. ⇒Round to the nearest whole number. Linear speed = ____ cm/s

Answers

Answer:

352 cm/s

Step-by-step explanation:

circ = 44pi

speed = distance * time

distance = circ * 4 = 176pi

speed = 176pi/0.5

Answer:

≈ 1106 cm/s

Step-by-step explanation:

linear speed = angular speed x radius of the rotation

v = ωr

v = linear speed (m/s)

ω = angular speed (radians/s)

r = radius of the rotation (m)

------------

Given:

d= 44 cm ⇒ r= 44/2 cm= 22 cmω= 4 rev/0.5 s= 8 rev/s= 8*2π/s= 16π/s  (converted rev to radians)

Linear speed is:

v= 22*16π cm/s ≈ 1106 cm/s (rounded to full number)

Juanita wants to buy 12.5 pounds of stones to decorate her garden. The stone normally sells for $1.80 a pound. The salesman offers her a total price of $21.25. How much is she saving per pound with the salesman’s offer? Round to the nearest hundredth.

Answers

Answer:

She is saving 10 cents per pound

Step-by-step explanation:

First, we need to find how much she would pay without the sale:

12.5(1.8) = 22.5

Now, we can calculate how much she saved:

22.5 - 21.25 = 1.25

To find how much she's saving per pound, we divide the difference by the number of pounds:

1.25/12.5 = 0.1

She is saving 10 cents per pound

Answer:

A

Step-by-step explanation:

I took the test and got it right

Evaluate. Write your answer as a fraction or whole number without exponents. 3^–3 =

Answers

Answer:

The answer is 1/27

Step-by-step explanation:

According to the rules of indices

a^-b can be written as 1/a^b

So 3^- 3 can be written as 1/3³

And

1/3³ = 1/27

Hope this helps you

Select the correct answer. If g = 8, what is the value of the expression g/2+3 ? A. 8/5 B.11/2 C. 7 D. 19

Answers

Answer:

7

Option C is the correct option

Step-by-step explanation:

g = 8 ( given )

Now,

[tex] \frac{g}{2} + 3[/tex]

Plugging the value of g

[tex] \frac{8}{2} + 3[/tex]

[tex] \frac{8 + 3 \times 2}{2} [/tex]

[tex] \frac{8 + 6}{2} [/tex]

[tex] \frac{14}{2} [/tex]

[tex]7[/tex]

Hope this helps...

Good luck on your assignment...

Look at the picture for the question ........................

Answers

Answer:

53/28

Step-by-step explanation:

100 g jam

19 g strawberries53 g blackberriesSugar= 100-(19+53)= 28 g

Blackberry / sugar= 53/28

Answer:

53:28

Solution,

Amount of sugar=100-(19+53)

=100-72

=28 gram

Ratio of blackberries to sugar=53/28

=53:28

Hope this helps..

Good luck on your assignment..

A group of 4 friends went to lunch and spent a total of $40, which included the $34 food bill and the tip. They decided to split the bill and tip evenly among themselves.

One of the friends used the equation One-fourth (t + 34) = StartFraction 40 over 4 EndFraction to represent the situation, where t represents the total amount of the tip. Which describes the amount each friend paid for the food and for the tip?

Answers

Answer:

The individually paid $1.5 for the tip and $8.5 for the food

Step-by-step explanation:

Total money spent =  $40

Food bill =  $34

if the situation is represented by the equation [tex]\frac{1}{4}(t+34) = \frac{40}{4}[/tex] where t is the amount of the tip, the amount for the tip can be calculated as shown;

[tex]\frac{1}{4}(t+34) = \frac{40}{4}\\ t+34 = 40\\t = 40-34\\t = 6[/tex]

Amount of the tip = $6

If they decided to split the bill and tip evenly among themselves, amount paid by each friend for the food and the tip can be gotten using the equation representing the situation where t = $6 as shown;

[tex]= \frac{1}{4}(t+34) \\= \frac{1}{4}(6+34)\\= \frac{1}{4}(6)+\frac{1}{4}(34)\\= 1.5+8.5\\[/tex]

From the result above, it can be seen that each friend paid $1.5 for their tip and $8.5 for their food

Answer:

A) Each friend paid $8.50 for the food and $1.50 for the tip.

A student earned grades of​ B, B,​ A, C, and D. Those courses had these corresponding numbers of credit​ hours: 4,​ 5, 1,​ 5, 4. The grading system assigns quality points to letter grades as​ follows: Aequals=​4, Bequals=​3, Cequals=​2, Dequals=​1, and Fequals=0. Compute the grade point average​ (GPA) and round the result to two decimal places.

Answers

Answer:

1.69

Step-by-step explanation:

Let the five courses with their corresponding credit hours be represented as shown;

FST 201 = 4

FST 203 = 5

FST 112 = 1

FST 219 = 5

FST 223 = 4

If a student earned grades of​ B, B,​ A, C, and D respectively in those courses with the following grading system  A =​4, B =​3, C =​2, D =​1, and F =0, before we can get the student GPA, we need to know the total credit point for the five courses.

Credit point for each course = Number of credit hour * point for each grade

FST 201 = 4 * 4 = 16points (A)

FST 203 = 5 * 4 = 20points (A)

FST 112 = 1 * 4  = 4points (A)

FST 219 = 5 * 4 = 20points (A)

FST 223 = 4 * 4 = 16points (A)

Total credit point = 16+20+4+20+16 = 76points

Total credit point gotten by the student is calculated as thus;

FST 201 = 4 * 3 = 12points (B)

FST 203 = 5 * 3 = 15points (B)

FST 112 = 1 * 4  = 4points (A)

FST 219 = 5 * 2 = 10points (C)

FST 223 = 4 * 1 = 4points (D)

Total credit point gotten by the student = 45points.

student's Grade Point Average​ (GPA) = Total credit point/Total credit point gotten by the student = 76/45 = 1.69 (to 2dp)


Find the value of x

Answers

Answer:

8

Step-by-step explanation:

the value of x is 8 because the sides are the same

Which of the following represents the ratio of the hypotenuse to the given side?

Answers

Answer:c

Step-by-step explanation:

hyp=6[tex]\sqrt{2}[/tex]

adj=6

hyp:adj=6[tex]\sqrt{2}[/tex]  :2

hyp:adj=[tex]\frac{6\sqrt{2} }{6} \\[/tex]

[tex]=\frac{\sqrt{2} }{1} \\hyp:adj=\sqrt{2} :1[/tex]

Write 6 17/20 as a decimal

Answers

Answer:

6.85

Step-by-step explanation:

6 17/20

Convert to improper fraction.

137/20

Divide.

= 6.85

Answer:

6.85

Step-by-step explanation:

17/20 = 85/100

17 x 5 = 85

20 x 5 = 100

so,

6 + 85/100 = 6.85

Sales personnel for Skillings Distributors submit weekly reports listing the customer contacts made during the week. A sample of 65 weekly reports showed a sample mean of 17.5 customer contacts per week. The sample standard deviation was 4.2.

Required:
Provide 90%90% and 95%95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel.

Answers

Answer:

Since the Confidence is 0.90 or 90%, the value of [tex]\alpha=0.1[/tex] and [tex]\alpha/2 =0.05[/tex], and the critical value would be [tex]t_{\alpha/2}=1.669[/tex]

And replacing we got

[tex]17.5-1.669\frac{4.2}{\sqrt{65}}=16.63[/tex]    

[tex]17.5+1.669\frac{4.2}{\sqrt{65}}=18.37[/tex]    

For the 95% confidence the critical value is [tex]t_{\alpha/2}=1.998[/tex]

[tex]17.5-1.998\frac{4.2}{\sqrt{65}}=16.46[/tex]    

[tex]17.5+1.998\frac{4.2}{\sqrt{65}}=18.54[/tex]    

Step-by-step explanation:

Information given

[tex]\bar X¿ 17.5[/tex] represent the sample mean

[tex]\mu[/tex] population mean (variable of interest)

s¿4.2 represent the sample standard deviation

n¿65 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The degrees of freedom are given by:

[tex]df=n-1=65-1=64[/tex]

Since the Confidence is 0.90 or 90%, the value of [tex]\alpha=0.1[/tex] and [tex]\alpha/2 =0.05[/tex], and the critical value would be [tex]t_{\alpha/2}=1.669[/tex]

And replacing we got

[tex]17.5-1.669\frac{4.2}{\sqrt{65}}=16.63[/tex]    

[tex]17.5+1.669\frac{4.2}{\sqrt{65}}=18.37[/tex]    

For the 95% confidence the critical value is [tex]t_{\alpha/2}=1.998[/tex]

[tex]17.5-1.998\frac{4.2}{\sqrt{65}}=16.46[/tex]    

[tex]17.5+1.998\frac{4.2}{\sqrt{65}}=18.54[/tex]    

which of the following descriptions represent the transformation shown in the image? Part 3c​

Answers

Answer:  c) rotation of 180° & shift right 1 unit and down 2 units

Step-by-step explanation:

Rotation of 180° changes the signs of x and y

(x, y)   →   (-x, -y)

Shift right one unit adds 1 to x, Shift two down subtracts 2 from y

(-x, -y)   →   (-x + 1, -y - 2)

  (x, y)          (-x + 1, -y - 2)  

(-1, -2)    →       (2, 0)

(-4, -1)    →       (5, -1)

(-4, -3)   →       (5, 1)

In the figure, a//b, and both lines are intersected by transversal t. Complete the statements to prove that m<1=m<5.

Answers

Answer:

Transitive Property of EqualityAlternate Interior Angles Theorem

Step-by-step explanation:

a) You're trying to justify that two sums equal to 180° are equal to each other. The Transitive Property of Equality is that justification.

__

b) You're trying to justify that angles 3 and 6 are congruent. These are between the parallel lines, so are "interior" angles. They are on opposite sides of the transversal, so are "alternate" angles. They do not share a vertex, so cannot be vertical angles. The applicable theorem is the Alternate Interior Angles Theorem.

Answer:

Step-by-step explanation:

For the data set represented by this box plot, what is the value of the maximum? maximum:

Answers

Answer:

140

Step-by-step explanation:

The maximum is the furthest the line that goes out the furthest, the minimum would be about 83-84

Answer:

the other person is correct!

Step-by-step explanation:

Kajol has $75. This is 3/8 of the amount she earned. How much did she earn?

Answers

Answer:

$200

I hope this helps!

Answer:

200rupees

Step-by-step explanation:

according to the question ,kajol has 75 rupees

amount earned=3/8* amount earned

                        =75/3*8

                         =200 rupees

Need Help!!!! What is 1495486+73940426 Thanks!

Answers

Answer:

75435912

Step-by-step explanation:

1495486+73940426

= 75435912

Answer:

75,435,912

Step-by-step explanation:

=> 1495486 + 73940426

Using Calculator

=> 75,435,912

5x is equal to 8X raise to power - 1/3​

Answers

Answer:

No solutions.

Step-by-step explanation:

5x = 8x^-1/3

Divide 8 into both sides.

5/8x = x^-1/3

Divide both sides by x.

5/8 = x^-4/3

Multiply both sides by the exponent -3/4.

5/8^-3/4 = x

1.422624 = x

Plug in 1.422624 for x to check.

It does not work. There are no real solutions.

Select all that apply. A direct variation equation is graphed. The point (6, 4) is on the graph. Which of the following points are also on the graph of the equation? (3, 2) (-9, -6) (-12, 8) (-6, -3)

Answers

Answer:

(3,2)

(-9,-6)

Step-by-step explanation:

Given that the graph is a direct variation.

The equation of variation is:

[tex]x=ky[/tex]

Since point (6, 4) is on the graph

[tex]6=4k\\\\k=\dfrac64[/tex]

Therefore, the equation connecting x and y is:

[tex]x=\dfrac64y[/tex]

[tex]\text{When y=2},x=\dfrac64 \times 2 =3\\\\\text{When y =}-6,x=\dfrac64 \times -6 =-9\\\\\text{When y =}8,x=\dfrac64 \times 8 =12\\\\\text{When y =}-3,x=\dfrac64 \times -3 =-4.5[/tex]

Therefore, the points that are also on the graph are:

(3,2) and  (-9,-6)

Answer:

(-9, -6) and (3, 2)

Step-by-step explanation:

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would you feel a sense of foreboding if a black cat crossed your path? Explain What is the result of subtracting the second equation from the first? 8x-4y=-4 -3x+4y=5 describe briefly one problem caused by the expansion of metals. Solve: 25x2 36 = 0. Place the following statements into the correct categories.Canal constructed to Red SeaThe Old KingdomProsperity and trade increasedGreat Pyramids were constructedKingdom fell to Hyksos invaders Given the venn diagram below, what is the correct notation? The technology environment would include studies of family changes. social engineering. information technology. minimum wage laws. customer service. Credit card A has an APR of 22.2% and an annual fee of $50, while credit cardB has an APR of 23.9% and no annual fee. All else being equal, at about whatbalance will the cards offer the same deal over the course of a year? O A. $2385.75B. $238.58O C. $23,857.48O D. $23.86 hy my frnds plzz help me in topic of" laws are never respected nor enforced in india" plzz write 1/2 pages essay plzz write in ur wording dont copy from net plzz it is resquest plzz write in ur wording plzz 0.00045-2.5*10^-5 in scientific notation? There are orange, yellow and blue sweets in a box. The ratio of thenumber of orange, yellow and blue sweets in the box is 7:5:4. Whatpercentage of the sweets are blue? *4%25%35%O 16% 10. If there is a crossword that has four squares that need to be filed, how many possible four letter arrangements are there (assuming they do not have to make a real word)? Use the given information to draw a box-and-whisker plot of the data setMinimum 28Maximum 54Lower Quartile 32Upper Quartile 40 In the past, 75% of the tourists who visited Chattanooga went to see Rock City. The management of Rock City recently undertook an extensive promotional campaign. They are interested in determining whether the promotional campaign actually INCREASED the proportion of tourists visiting Rock City. The correct set of hypotheses is _____. A company has net income of $940,000; its weighted-average common shares outstanding are 188,000. Its dividend per share is $0.85, its market price per share is $96, and its book value per share is $88.00. Its price-earnings ratio equals? Solve for f. -11f=7(1-2f)+5 A company's days' cash on hand is computed by dividing: Group of answer choices cash and short-term investments by daily cash operating expenses. cash by total cash operating expenses. cash, short-term investments, and accounts receivable by daily cash operating expenses. average cash over the period by daily cash operating expenses. Write In (4/9) in terms of In 2 and In 3.A)21n 2 - 21n 3B)4In 2 - 4In 3C) 3(In 2 - In 3)D)In2 2 - 4In 3 geometry! please help How many different 7-digit PIN codes using only the digits 0-9 are possible?