Combustion by moving pistons which respond to a change in pressure.
heat engines
refrigeration units
furnaces
heat pumps

The correct answer is heat engines.

Explanation:

Heat engine is a device that uses heat to perform some work. Heat engine consists of a gas present in the cylinder with piston.

If a gas is heated then the gas will expand. Then the piston moves up. If the gas is cooled down then the piston moves backward. There is a cycle of heating and cooling which leads to move the piston up and down due to change in pressure.

Therefore, heat engines use combustion by moving pistons which respond to a change in pressure.

harry byrd declared organized resistance by southern states would prevent racial integration.

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods