Roberto stepped onto the hot sand at the beach. Realizing it was hot, he quickly moved to the shaded area. Which two systems worked together to move him safely into the shade so that he doesn't hurt his feet? * A) Nervous and muscular

or

B) Nervous and cardiovascular

Astudent wants to test the hypothesis that fertilizer improves the growth rate of grass seeds. to test this hypothesis, the student put the same amount of grass seed in 3 containers with the same type of soil. the student measured the growth at the end of the week. all plants received equal amounts of water and sunlight. if you were asked to graph this data, what would you place on the x-axis? a. fertilizer b. water c. plant growth d. week one