Suppose you want to test the hypothesis that plants grow taller when they receive more sunlight. Identify an independent variable and a dependent variable for this investigation. Explain your reasoning.

Independent variable: the different amounts of sunlight given to plants
Dependent variable: the height of the plant
Because the independent variable is what you change in the experiment and the dependent variable is what is affected by the independent variable

It's either -limiting factors or -scarce resources but i'd go with my first answer since the food and water are abundant they really aren't scarce

Ibelieve the answer is relative humidity  because it makes more sense that way. solar flares usually occur in space it doesn't affect the earth, well it could but it wont make a significant damage.  latitude is land it doesnt do anything. prevailing winds, i dont know the correct meaning for this but i doubt that affects the land so it has to be relative humidity.