Why did scientists choose carbon as a base for the atomic mass unit? which isotope of carbon did they use?

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Asystem containing an ideal gas at a constant pressure of 1.22×10^5 pa gains 2140 j of heat. during the process, the internal energy of the system increases by 2320 j. what is the change in volume of the gas?

The slope of a velocity time graph over any interval of time gives the during that interval