The "ingredients" of photosynthesis are carbon dioxide and

“ingredients” for photosynthesis are carbon dioxide, water, and light energy.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

idk what the options are but

these is a strong electrostatic attraction between the ions hence a lot of energy is needed to overcome this attraction

this is why the boiling points are so high