you've made the hypothesis that the less rainfall a cactus plant gets, the taller it will grow, since cactuses like dry conditions.
what should be the independent variable in an experiment designed to test this hypothesis?
a. the height of the cactus plants
b. the hours of sunlight the cactus plants get
c. the amount of rain falling on the cactus plants
d. the type of soil the cactus plants are growing in

Drag each tile to the correct box. the body monitors the levels of oxygen in the blood to regulate breathing. isabel is running in a marathon and is near the finish line. she feels out of breath. how will her nervous system work to generate a reaction? arrange the tiles in chronological order. isabel's breathing rate increases. sensory receptors in the arteries detect low oxygen levels. the brain sends signals through motor neurons. sensory neurons generate an impulse. the central nervous system relays an impulse to certain brain regions.

What methods do scientists use to predict volcanic eruptions? select all that apply

The diagram is represented of a part of a plant cell. identify the locations where proton concentration builds up during photosynthesis and cellular respiration