Out of battery, conductor, lightbulb, and switch which of these are sources of energy

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems

Amoeba proteus is injected with a drug that inhibits the formation of microtubules. what effect does this have on the organism’s movement?

Select the correct answer. which of the following statements is a scientific claim? a. the early solar system had large amounts of water; so, the oldest objects in the solar system should also be abundant in water. b. the mass of the universe is much greater than current models predict; it is not possible to explain this inconsistency. c. planet earth is abundant in water, but there is no way to scientifically determine from where earth's water originated. d. earth is shaped like a sphere even if not all of the scientific observations related to its shape support this idea.