How do plants adjust their behahvior related to gravity, light and touch?

What are similarities and differences between refraction, reflection, diffraction and absorption?

It is really hard for me right know

When conducting an investigation to determine which type of fertilizer produces the most flowers on a plant, which variable would be graphed on the x-axis once you collected the data? a. type of fertilizer b. amount of flowers c. amount of water d. number of days that the plants grew