How many star are thier in the universe

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Apulley system is used to lift a 2,000 newton engine up a distance of 3 meters. the operator must apply a force of 250 newtons to the chain of the pulley system to lift the motor. to lift the engine 3 meters, the operator must pull a total of 30 meters of chain through the pulley system. what is the value of di?

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2