Use the information to answer the following question. Hot air balloons use a flame that can turn on and off to heat air inside a large balloon. The balloon is attached to a basket which can carry
people or cargo as it is lifted off the ground and floats in the air.
Using what you know about gases, predict which approach would allow the hot air balloon to reach the highest height?
O A. Turn on the flame for 10 seconds each minute for 2 minutes, and cut a large hole in the balloon material to allow excess air out.
OB. Turn on the flame for 30 seconds each minute for 10 minutes to decrease the density of the air inside the balloon.
O C. Turn on the flame for 30 seconds each minute for 2 minutes, and cut a large hole in the balloon material to allow excess air out.
OD. Turn on the flame for 10 seconds each minute for 10 minutes to increase the density of the air inside the balloon.

If this plastic cup is heated to its melting point, what will eventually happen to all the particles in the plastic? a. the particles will begin to move enough that they slide past each other. b. bonds will form and the liquid will become a solid. c. the spaces between the particles will get smaller. d. the particles will change state and become a crystalline solid.

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