Which of the following is a shape that has two foci?
A. A ray
OB. A sphere
O C. A circle
D. An ellipse

Answers

Answer 1

Answer:

It is D.

Explanation:


Related Questions

What are ancient plants and animal formed into rocks called it is a 7 letter word that starts with f

Answers

Answer:

Fossils

Explanation:

Ancient plants and animal formed into rocks called fossils.

A fossil can be defined as the mineral impression or remains of living organisms such as plants and animals that are prehistoric in nature.

A geologic column can be defined as a collection of rock layers that are typically grouped based on their relative ages in a descending order i.e from oldest to the youngest.

Generally, the layers of the rock that are found in various parts of the world are known to be different because they all comprises of distinct Earth's geological history (fossils).

A student investigates a pure metal, X . The student takes a 100.0 g piece of metal X , heats it to 500.0°C , then places it on a 1000.0 g block of ice at 0.0°C . The ice partially melts, and the final temperature of the metal, ice, and melted water is 0.0°C . The student calculates the experimental value of the specific heat capacity of metal X and records it as 0.24 J/(g⋅°C) . Calculate the magnitude of the energy change (qmetal) of metal X during the experiment.

Answers

Answer:

q_metal = -12000 J = -12 KJ

Here, the negative sign indicates that the energy is lost by the metal piece.

Explanation:

The magnitude of energy change of the metal X can be given by the following formula:

[tex]q_{metal} = mC\Delta T[/tex]

where,

m = mass of metal = 100 g

C = Specific Heat Capacity of metal X = 0.24 J/g.°C

ΔT = Change in Temperature of Metal Piece = 0° C - 500°C = -500°C

Therefore, using these values in the equation, we get:

[tex]q_{metal} = (100\ g)(0.24\ J/g^oC)(-500^oC)\\[/tex]

q_metal = -12000 J = -12 KJ

Here, the negative sign indicates that the energy is lost by the metal piece.

A closed gas system initially has volume and pressure of 6400mL and 1.49atm with the temperature unknown. If the same closed system has values of 657 torrs, 9660mL, and 2450C, what was the initial temperature in K?

Answers

Answer: The initial temperature was 588 Kelvin

Explanation:

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas = 1.49 atm

[tex]P_2[/tex] = final pressure of gas = 657 torr = 0.864 atm   (760 torr = 1atm)

[tex]V_1[/tex] = initial volume of gas = 6400 ml

[tex]V_2[/tex] = final volume of gas = 9660 ml

[tex]T_1[/tex] = initial temperature of gas = ?

[tex]T_2[/tex] = final temperature of gas = [tex]245^0C=(245+273)K=515K[/tex]

Now put all the given values in the above equation, we get:

[tex]\frac{1.49\times 6400}{T_1}=\frac{0.864\times 9660}{515}[/tex]

[tex]T_1=588K[/tex]

The initial temperature was 588 Kelvin

An 8.5 g. Of ethanol (C2H5OH) placed in a constant volume calorimeter and the temperature rose to 3.2°C. Find the heat of reaction of the ethanol (MM =46.1 g/mol) in kJ/mol. The heat capacity of the calorimeter plus water is read as 6.38 J/°C

Answers

Answer:

[tex]\Delta H_{rxn}=-0.111 \frac{kJ}{mol}[/tex]

Explanation:

Hello!

In this case, since the total heat flow due to the reaction equals the negative of the calorimeter's heat, we can first compute the former as shown below:

[tex]Q_{rxn}=-C\Delta T\\\\Q_{rxn}=6.38\frac{J}{\°C}*3.2\°C=-20.416J[/tex]

Now, since this total heat flow due to the reaction is defined in terms of the heat of reaction and the total reacted moles:

[tex]Q_{rxn}=n*\Delta H_{rxn}[/tex]

Thus, we compute the moles in 8.5 g of ethanol:

[tex]n=8.5g*\frac{1mol}{46.08g}=0.185mol[/tex]

Therefore, the heat of reaction results:

[tex]\Delta H_{rxn}=\frac{Q_{rxn}}{n} =\frac{-20.416J}{0.185mol} =-110.7J/mol\\\\\Delta H_{rxn}=-0.111 \frac{kJ}{mol}[/tex]

Best regards!


A teacher tells the student to dlaw the same wave with double the frequency, while keeping the amplitude the same. How would the student draw the new wave?

Answers

Answer:

A.

Explanation:

Frequency is how often one complete cycle or wave takes place. Amplitude is the height of the wave from the midpoint to the crest.

The new drawing should have twice as many waves in the same period of time, with the same height wave.

Answer:

A.)

Explanation:

Frequency is how often one complete cycle or wave takes place. Amplitude is the height of the wave from the midpoint to the crest.

The new drawing should have twice as many waves in the same period of time, with the same height wave.

1. Which of the five types of reactions is taking place in the whoosh bottle? Justify your answer with evidence from the video.

Answers

Answer:

Other times I place a candle in water and cover it with a glass jar  .

Explanation:

only to ... Many of you may already know this as the Whoosh Bottle demo due ... I have used this demo in the past for topics like exothermic reactions, combustion reactions, ... This adds to the evidence of a partial vacuum created in the bottle

11.
Which of these statements is true about the two graphed parallelograms?
A
B
8
6
A
4
B'
D
C
2
D
C'
-6
2
4
6
-2.
-2
-4
-6
-8 +
A
They are similar, because one can be obtained by dilating the other about the origin with a scale factor of

Answers

Answer:

Explanation:

dfghyuiop[]5565677dam u baddie no comparing

How many moles are in 58.6 L of N2gas at STP?

Answers

n equals 2.62 hope this helps

Answer:

[tex]\boxed {\boxed {\sf 2.62 \ mol \ N_2}}[/tex]

Explanation:

The relationship between moles and gases is unique. Regardless of the type of gas, there will always be 22.4 liters of gas in 1 mole, as long as it's at STP (standard temperature and pressure).

We can make a ratio using this information.

[tex]\frac {22.4 \ L \ N_2}{ 1 \ mol \ N_2}[/tex]

Multiply by the given number of moles.

[tex]58.6 \ L \ N_2 *\frac {22.4 \ L \ N_2}{ 1 \ mol \ N_2}[/tex]

Flip the fraction so the liters of nitrogen cancel.

[tex]58.6 \ L \ N_2 *\frac {1 \ mol \ N_2}{ 22.4 \ L \ N_2}[/tex]

[tex]58.6 *\frac {1 \ mol \ N_2}{ 22.4 }[/tex]

[tex]\frac {58.6 \ mol \ N_2}{ 22.4 }= 2.61607143 \ mol \ N_2[/tex]

The original measurement of liters has 3 significant figures, so our answer must have the same.

For the number of moles calculated, 3 sig figs is the hundredth place. The 6 in the thousandth place tells us to round the 1 to a 2.

[tex]2.62 \ mol \ N_2[/tex]

58.6 liters of N₂ gas at STP is equal to about 2.62 moles.

does anyone have the gizmo cell types answer key for activity d?

Answers

Answer:

im sorry i dont

Explanation:

write the electronic configuration of an Na+ and CL-1​

Answers

Answer:

Na+ lost one electron:    1s2 2s2 2p6

Cl- gained an electron:   1s2 2s2 2p6 3s2 3p6

Explanation:

Is the fractional distillation of liquefied air a physical or chemical change?

Answers

Fractional distillation involves 2 main stages and both are physical state changes. It can only work with liquids with different boiling points but the boiling points can be quite close together.

Answer:

Physical Chanhe is the answer : )

Give me lil reasoning so I know your not lying for points
:(
(I’ll mark you as brainlister )

Answers

Answer:

C

Explanation:

An inverse relationship means that as one increases the other decreases. From the negative slope of this graph, you can tell that as volume increases, pressure decreases. If you look at the data point for 20 on the volume axis, it matches up with about 240 on the pressure axis.

Calculate the molarity of a solution containing 21.9g of MgCl, in enough water to
make a 750.mL solution.

Answers

Find moles of MgCl first by dividing by the molar mass.

21.9 g / 95.211 g/mol = 0.230 mol MgCl

Then divide by L of water to get the molarity.

0.230 mol / 0.750 L = 0.307 M MgCl



The teacher asked the students to design an experiment that would demonstrate that temperature will affect the pressure of a gas. Which of the
following would be a valid experiment that shows the correct relationship between gas temperature and pressure?

Answers

The correct option is option A. when the students check the air pressure of bicycle tires, once by keeping it out in the winter and noticing the air pressure being decreased and after by keeping the bicycle inside at room temperature and noticing that the air pressure has increased.

How are pressure and temperature of a gas related ?

According to Gay lussac's law, the temperature and pressure of a gas are directly proportional to each other, provided the volume is constant.

When the temperature of a gas is increased, the molecules gain more kinetic energy and hence the frequency of them hitting the walls of the container increases which basically implies that the pressure increases.

On the other hand when the temperature is low, the molecules do not have substantial kinetic energy to hit the walls of the container frequently, that is the pressure decreases.

 

When the bicycle tires were kept out in the winter, the low temperature decreased the air pressure inside the tires. While when they were warmed at room temperature, the pressure inside the tires increased.

Therefore, the correct option is option A.  when the students check the air pressure of bicycle tires, once by keeping it out in the winter and noticing the air pressure being decreased and after by keeping the bicycle inside at room temperature and noticing that the air pressure has increased.

   

To know more on Gay lussac's law, click on

https://brainly.com/question/30758452

#SPJ2  

True or false: Sometimes older rocks end up on top of younger rocks.

Answers

Answer:

true

downstream to the riverbed. However, the most common mechanism to produce older rocks on top of younger is by thrust faulting. Thrust faults form where rocks are being compressed, usually by plate tectonic mechanisms. Thrust faults rip up older strata and pile it on top of younger rocks.

Explanation:

true you’re welcome

A student runs 100 meters in 16 seconds. What is the speed of the student?

Answers

Answer:

6.25m/s

Explanation:

speed = distance/time

speed = 100/16 = 6.25m/s

HELP WITH THIS WORD PROBLEMStudents want to gather evidence for the claim that the number of atoms present before a chemical reaction is equal to the number of atoms present after the chemical reaction. They decide to react vinegar and baking soda in a sealed plastic bag. Which of the following would provide the evidence the students need?
The mass of the plastic bag, baking soda, and vinegar before the reaction was equal to the mass after the reaction.
Bubbles were produced during the reaction, which meant that a gas was being produced
.The plastic bag did not change in any way, indicating that it was not involved in the reaction.
The mass of the baking soda was exactly equal to the mass of the vinegar used to create the chemical reaction.

Answers

The mass of the plastic bag, baking soda, and vinegar before the reaction was equal to the mass after the reaction.

Conservation of atoms is just conservation of mass.

Water conservation is important for which of the following reasons?

A. Demand for water is increasing.

B. Water treatment is expensive.

C. Pollution is likely to decrease water supply in the future.

D. All of the above

Answers

D

all of above becuase it's all conservation

Answer:

The answer is c which is pollution is likely to decrease water supply in the future

40 points
I have 400 mL of a 0.2 M simple syrup solution (made up of just sugar and water) that I want to boil down to result in a solution with a concentration of 0.5 M. How many milliliters of water would I need to evaporate?

Answers

Answer:

2000ml

Explanation:

you multiple 400ml with 0.5 ml to get the required meter for the water that needs to be evaporated

Calculate the change in heat (Q) that occurs when 7.58grams of steam at 101°C cools to liquid water at 40°C. (cp = 4.184 J/g°C)

Answers

Answer:

Q = 19065.4 J

Explanation:

Q₁ = the required energy for phase change of H₂O from vapor to liquid

Q₁ = mass of H₂O * heat of vaporization

Q₁ = 7.58 g * 2260 J/g

Q₁ = 17130.8 J

Q₂ = energy required to cool the water fro 101°C to 40°C

Q₂ = mass of H₂O * specific heat of H₂O * ΔT

Q₂ = 7.58 × (4.184 J/gC) × (101 - 40)

Q₂ = 1934.6 J

Q = Q₁ + Q₂

Q = (17130.8 + 1934.6) J

Q = 19065.4 J

How does a hydroelectric power plant convert energy?

A. As water flows through the channels toward the turbines, it has kinetic energy. This is changed to mechanical energy as the water turns the turbines. Then the mechanical energy of the turbines is changed to electrical energy by the generator.
B. As water flows through the channels toward the transformer, it has potential energy. This is converted to electrical energy by the transformer, and then the energy is magnified by the generator.
C. As water flows through the channels toward the generator, it has potential energy. This is changed to electric energy as the generator rotates. Some of the electric energy is used to change water's energy into kinetic energy.
D. As water flows through the channels toward the turbine, it has kinetic energy. This is changed to potential energy within the turbine. This potential energy is converted to electrical energy by the transformer.

PLS HELP I WILL GIVE BRAINLYIST!!!

Answers

The answer is c I know because I did did yesterday

Who is wise president of india?
________________________​

Answers

The vise president of India is M. Venkaiah Naidu

answer pls ill give brainly
How is energy from the sun used as food energy by organisms in an ecosystem?
Energy from the sun is absorbed as heat by consumers.
Energy from the sun is absorbed by fungi, and it is then passed on to consumers.
Energy from the sun is converted into food energy by producers, which is then passed on to consumers.
Energy from the sun is converted into food by consumers, which is then passed on to producers.

Answers

Answer:

its absorbed by heat from consumers

WILD GUESS
OUT OF BAKUGOU SHOTO AND DEKU


GUESS WITCH ONE I SIMP FOR

Answers

Answer: all of them?

Explanation:

Answer:

Deku.

Explanation:

When a 8 gram slice of bread is burned under a beaker of 4500 grams of water, it heats up the water by 1.3 degrees Celsius. The specific heat of water is 1 cal/g degree C. How many calories does this slice of bread contain

Answers

Answer:

[tex]5850\ \text{cal}[/tex]

Explanation:

m = Mass of water = 4500 g

c = Specific heat of water = [tex]1\ \text{cal/g}^{\circ}\text{C}[/tex]

[tex]\Delta T[/tex] = Change in temperature of water = [tex]1.3^{\circ}\text{C}[/tex]

Heat is given by

[tex]q=mc\Delta T\\\Rightarrow q=4500\times 1\times 1.3\\\Rightarrow q=5850\ \text{cal}[/tex]

A slice of the bread contains [tex]5850\ \text{cal}[/tex].

please help!! will give brainliest if u tell me how
Why does heat transfer from object to object?
Select one:
a.Heat transfers because of the temperature differences between objects
b.Heat transfers because of the mass difference between objects
c.Heat does not transfer between objects
d.Heat is energy so it moves

Answers

i am pretty sure it’s A

why do scientist think the earths core have iron in it .

Answers

because to protect the earth since it’s round and big

In a warehouse, the workers sometimes slide boxes along the floor to move them. Two boxes were sliding toward each other and crashed. The crash caused both boxes to change speed. Based on the information in the diagram, which statement is correct? In your answer, explain what the forces were like and why the boxes changed speed.

Box 1 has more mass than Box 2.
Box 1 and Box 2 are the same mass.
Box 1 has less mass than Box 2.

Answers

Answer:

Box 1 and Box 2 are the same mass.

Explanation:

Because they both change speed due to having the same mass!

Hope this helps! :) BRAINLIEST PLZ

Cuáles son el pHy PoH de una solución cuya concentración de iones hidronio [H+]es de 0.000475 M de acido sulfurico?

Answers

El ácido sulfúrico es un ácido fuerte y por eso disocia completamente. La concentración de H+ será igual a la concentración de ácido sulfúrico (0.000475 M).

Para encontrar el pH, calcula -log[H+] = -log(0.000475) = 3.323

Para encontrar el pOH, sabes que pH + pOH = 14, y por eso pOH = 14 - pH = 14 - 3.323 = 10.677.

Help please
what is the half-life of c-14 at 250g?

Answers

Answer:

5,730 years

hope im right

Explanation:

Its half-life is 5,730 years. How much of a 250g sample of carbon-14 will be left in 5,000 years?

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UM, math question on area Car A travels 20 mph faster than Car B. In the same time that Car A travels 208 mi, Car B travels 156 mi. Find their speeds. The speed of Car A is and the speed of Car B The figure below shows a shed in the shape of a rectangular prism.Note that the shed has a floor. How does setting a work of drama in the past help drive the action of the story forward? -The events of the past cause the events in the story to unfold. - It's easier to tell stories set in the past because everything already happened. -Old stories are enjoyed more by most people. - Stories about wars are always popular. Yesenia buys milk to make milkshakes for all her friends. She buys 1 quart of milk and 1/2 gallon of milk. How many cups of milk does she buy? How many grams of oxygen are produced when 3.0 moles of potassium chlorate decompose completely? Read this claim from paragraph 3:Computers would also help kids apply for schools and jobs.Why is this claim reasonable? Helppppp what is the answerrrr???? 2.In ABC, BD is perpendicular to AC. The dimensions are shown in centimeters.What is the length, in centimeters, of AC?ASAP BEFORE TOMORROW 11 PLEASE THIS IS SOOOO LATE LOLOLIn a(n) _____the air mass does not move. Ayuda es para un examen Marcy is making a hooked circle-shaped rug for her mother. The circumference of the circle-shaped rug is 56.52 inches.What is the area of the rug? (Use 3.14 for .) A. 28.26 in2 B. 154.34 in2 C. 254.34 in2 D. 508.68 in2 Question 7 (2 points)The note below has a special name. Which is? How many distinct positive integer-valued solutions exist to the equation (x2 - 7x + 11)(x2 - 13x + 42) = 1 Look at the two rectangles on the centimetre square grid.BAa)Which rectangle (A or B) has the larger area? ab) Explain how you know. 3Which of the following is best described as part of the rising action of the story?AMom dances a little bit to the music.BMom becomes a good neighborCThe Spellmans give mom their spare tire.DMom shames them for missing mass when a rancher puts cattlein a pasture , what happens to the amount of grass in it Please really need help on this please What do people who use American Sign Language and people who use spoken language have in common?A.They express most of their emotions through therfaces and body.B.The mostly taken therhands. C.They fail to use e conteso when they speak. What are the characteristics of the graph of the inequality x>-2