Aheat engine does 300 j of work during one cycle. in this cycle 900 j of energy is wasted.
what is the efficiency of the engine?
a. 0.25
b. 0.33
c. 0.50
d. 0.75

This is the substance(s) formed in a chemical reaction.

The flame produced by the burner of a gas (propane) grill is a pale blue color when enough air mixes with the propane (c3h8) to burn it completely. for every gram of propane that flows through the burner, what volume of air is needed to burn it completely? assume that the temperature of the burner is 195.0°c, the pressure is 1.05 atm, and the mole fraction of o2 in air is 0.210.

The center of the milky way most likely contains a. empty space. b. a red giant star. c. a globular cluster. d. a supermassive black hole.