Automobile engines are . a. internal combustion engines b. external combustion engines c. heat pumps d. heating systems

a. internal combustion engines

Explanation:

Automobile engine are engines that requires the fuel to be burn at highest possible temperature to be able to provide torque to the engine and then to the wheel of the vehicle. Internal Combustion is made possible through the use of Spark Plug, Piston, Fuel (Petrol or Diesel). All these process occur in the Engine Cylinder.. The more and powerful the Piston in the Cylinder, the higher the energy the engine will generate.

a charge 3q is at the origin, and a charge −2q is on the positive x axis at x=a. part a where on the x-axis would you place a third charge so it would experience no net electric force? enter an expression for the exact answer, which will involve a square-root sign. (do not enter an approximate decimal answer.)

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up