Q: What property of propane does Rodriguez change using the burner? Support your answer with evidence from the text.
T: The wind is starting to blow stronger, and when you’re riding in a basket under a hot air balloon, just 400 feet above ground, that’s not necessarily a good thing. Keith Rodriguez looks to the horizon and squints. He had planned to take off from Scioto Downs, a horse racetrack south of Columbus, Ohio, fly a few miles north, and land his balloon in a barren cornfield next to his pickup truck.

Then the wind changed. Instead of a light breeze from the south, now Rodriguez’s bright red balloon is getting hit by stronger, colder winds headed west. He has plenty of propane fuel in his tank—he probably could ride the wind halfway to Pennsylvania. But that would be dangerous. Rodriguez’s choice of landing sites just became very limited. As the balloon switches direction and floats east, everything below becomes a wide carpet of suburban sprawl—big-box stores, major highways, and strip malls. Beyond the stores lie forests.

The only factor in Rodriguez’s favor is that it’s early, just after 7 a.m. The highways are filling up with people driving to work, but otherwise the morning is quiet and still.

“Oh boy,” Rodriguez thinks. “If I don’t land, like now, this could get bad.”

The balloon has no propeller or engine, so Rodriguez can’t change direction on his own—he’s entirely dependent on the wind. The only thing he controls is altitude. He does this by changing the air temperature inside the balloon.

Sitting on the floor of the wicker gondola are three tanks of liquid propane. The tanks are connected via black rubber hoses to two burners overhead. Each burner is nearly as big as Rodriguez’s head. Rodriguez turns a knob on one side of the burners. This releases propane from a tank into the heating coil, where the liquid propane is heated to a gas and mixed with the air. Then the mixture is ignited by a pilot light. The mixture catches fire, and flames leap two feet high into the balloon.

The balloon rises. Rodriguez has a plan in mind. The flame heats the air inside the nylon balloon. This works on a simple principle: hot air is lighter than cold air. One cubic foot of air weighs about an ounce. If you heat that air by 100 degrees Fahrenheit, its weight drops by about 7 grams. This means every cubic foot of heated air inside Rodriguez’s balloon can lift about 7 grams. Just by himself, Rodriguez weighs 170 pounds, which equals about 77,110 grams. That means he needs about 11,016 cubic feet of hot air just to raise his own body off the ground. This is why hot air balloons are so big—they must trap tremendous amounts of heated air. Rodriguez’s balloon is a common size, trapping about 100,000 cubic feet of air. The balloon is 80 feet tall and 60 feet wide. As Rodriguez gives his short burst of flame, the air inside swirls in complicated, invisible patterns.

To drop in altitude, Rodriguez can pull a cord attached to a parachute valve at the very top of the balloon. Since the hottest air sits at the top, this releases the balloon’s most buoyant air, which makes the balloon descend.

Rodriguez gives the cord a short pull, and the gondola drops a little.

“I don’t have an altimeter, and I can’t really see anything happening inside the balloon,” Rodriguez thinks. “I have to pilot by feel.”

Pushed by the wind, the balloon is flying quickly now. It’s floating over the back wall of a supermarket when Rodriguez grabs hold of the parachute valve cord and gives it a long, hard tug. The balloon drops. Quickly. The hot air balloon is sinking, but still flying forward.

It looks as though it’s about to slam into the edge of the supermarket’s roof, but it sails over it, with only about 15 feet to spare. Still, Rodriguez does not let go of the cord. He drops and drops, right between the light poles of the nearly empty parking lot. Just a few feet above the ground, Rodriguez releases the parachute cord, turns the knob above his head and fires both burners. The steep descent slows. The gondola touches lightly against the asphalt, and then drags to a stop. There are only two people in the parking lot, standing near the entrance to the store. They look toward the balloon, their eyes and mouths open wide in shock.

“That was a little closer than I expected,” Rodriguez says to himself, laughing. “I really needed to land quick.”

Answer:

The wind is starting to blow stronger, and when you’re riding in a basket under a hot air

balloon, just 400 feet above ground, that’s not necessarily a good thing. Keith Rodriguez looks

to the horizon and squints. He had planned to take off from Scioto Downs, a horse racetrack

south of Columbus, Ohio, fly a few miles north, and land his balloon in a barren cornfield next

to his pickup truck.  

Then the wind changed. Instead of a light breeze from the south, now Rodriguez’s bright red

balloon is getting hit by stronger, colder winds from the west. He has plenty of propane fuel in

his tank—he probably could ride the wind halfway to Pennsylvania. But that would be

dangerous. Rodriguez’s choice of landing sites just became very limited. As the balloon

switches direction and floats east, everything below becomes a wide carpet of suburban

sprawl—big‐box stores, major highways, strip malls. Beyond the stores lie forests.

Explanation:

PLS HELP!
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Read the article excerpt below then answer the question.
How does burning carbon-containing fuels contribute to Earth’s climate change problem?
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biodiversity
Project: Examining biodiversity and Ecosystem Services Active....
At least 6 slides
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• Slide 2 lists the land use ideas that the group considered
• There is at least 1 slide that describes and explains:
the land use plan that the team selected
how the selected land use plan will promote soil stability and encourage biodiversity
some of the materials needed for the selected land use plan and some relative costs
how the selected land use plan will provide benefits the citizens of Diversitopia

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It makes an ecosystem stable.


It isn't important in an ecosystem.


It makes a food chain crumble.

Can someone help me pls i understand if you don't know too DONT SEND IN LINKS THO

I am late on an assignment guys pls help

BRAINLIEST IF CORRECT





10

GIVING BRAINLIEST CORRECT ANSWER
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Made of multiple cells
Made in cones
Made in flowers
Made in single cells

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2. How can different structures perform the same function?

Please help! And explain your answer with evidence please!

What is it called when a plant’s embryo begins to grow?
photosynthesis
pollination
fertilization
germination

Brainliest if CORRECT






11

Need water cycle project ideas. I need to make a video about the water cycle for my teacher but i dont have any ideas.And, i do have other people to use in the video. If i give you the brainly that means im using your idea. The idea MUST BE about the water cycle. PLEASE HURRY!!

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Defenses such as your skin respiratory system, digestive and circulatory system
1. First Line
2. Allergy
3.T cell

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I need help with 23 and 24!

Why is biodiversity important?



It makes an ecosystem stable.


It isn't important in an ecosystem.


It makes a food chain crumble.

please help-
thank you-

Water off the coasts of some continents is typically colder than water further offshore because…
A. What evidence have you discovered to explain why air flows?
B. What evidence have you discovered to explain why Earth has global wind systems?
C. What evidence have you discovered to explain why ocean waters flow?
D. What evidence have you discovered to explain how wind influences the movement of water?
And for the Summary.
Water off the coasts of some continents is typically colder than water further offshore because...

Matter is made up of particle. Which of the following statement is true about these particle? A. A partical that make up soild do not move B. The partical that make up liquied do not move C The particals that makes up all matter D Only the parcicals that make up gaeses are constanlly in motion

Hello,

So I was wondering if this is correct... Is it?

Matter is made up of particle. Which of the following statement is true about these particle? A. A partical that make up soild do not move B. The partical that make up liquied do not move C The particals that makes up all matter D Only the parcicals that make up gaeses are constanlly in motion

Use the image to answer the question.
Emily and her science lab partner made a complete circuit by attaching a light bulb to some wires and a battery. Which of the following best describes the flow of energy in the complete circuit?
A. lightbulb, wire, battery, lightbulb, wire
B. battery, wire, lightbulb, wire, battery
C. battery, lightbulb, battery, lightbulb
D. wire, battery, wire, battery

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The temperature decreases by degree Celsius every hour?