Given a scientific passage and an answer, generate a question for the given answer.

[Q]: Passage: Not all wetlands are alike, as you can see from Figure below . Wetlands vary in how wet they are and how much of the year they are soaked. Wetlands also vary in the kinds of plants that live in them. This depends mostly on the climate where the wetland is found. Types of wetlands include marshes, swamps, and bogs. Answer: wetlands
[A]: Marshes, swamps, and bogs are types of what?

[Q]: Passage: Power plants are where electric power originates. They have electric generators that generate electric current through electromagnetic induction. Answer: power plants
[A]: Where does electric power originate?

[Q]: Passage: Look at the wheelbarrow in the Figure below . It is used to carry heavy objects. It consists of two simple machines: a lever and a wheel and axle. Effort is applied to the lever by picking up the handles of the wheelbarrow. The lever, in turn, applies upward force to the load. The force is increased by the lever, making the load easier to lift. Effort is applied to the wheel of the wheelbarrow by pushing it over the ground. The rolling wheel turns the axle and increases the force, making it easier to push the load. Answer: lever
[A]:
What simple machine works with a wheel and axle in a wheelbarrow?