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

Elements and compounds are pure substances that cannot be broken down physically into a simpler substance. a physical change doesn’t break the bonds between atoms of a substance or form new ones. compounds can be broken down by a chemical change. a chemical change breaks chemical bonds and/or forms new ones between atoms of a substance. what simple substance would a compound break into? the basic elements that make it up! for example, if you passed a very strong electric current through water you’d break the chemical bonds in water and be left with oxygen and hydrogen. which of the following is an example of a chemical change? a separating water into different glasses b breaking frozen ice cubes with a hammer c running an electric current through water d boiling water to evaporate it on a stove

The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.

In which terrestrial biome can you find trees that produce cones instead of flowers and needles instead of leaves? have trees that produce cones instead of flowers and needles instead of leaves. the latitudes in this biome have evenly distributed precipitation throughout the year. is it high or low