Producers use energy from the sun to create​

Photosynthesis

Explanation:

In photosynthesis, producers combine carbon dioxide, water, and sunlight to produce oxygen and sugar (their food). Other organisms get energy by eating producers.  It cannot directly use the Sun's energy to make food. As a consumer, it has to eat— or, consume— other organisms for energy.

a) A lightly inflated balloon is placed in a freezer: the size will decrease.

b)if it was instead kept outside in the sun for some time: the size will increase.

Explanation:

a) When we keep an inflated balloon in a freezer, it means we are keeping the balloon at lower temperature. According to kinetic molecular theory, if we decrease the temperature of gas sample, the kinetic energy of molecules will decrease, and they will move less randomly. The space between them will decrease, and the volume of the gas will decrease. This makes the size of balloon to decrease.

b) in second case, if we keep it in sun, the temperature will increase. The increase in temperature will increase the kinetic energy of molecules and thus molecules will move more randomly. The space between them will increase, this will increase the volume.

In extreme case the balloon may burst even.