Abook on a 2 meter high shelf has 20 joules of potential energy. what is the mass of this book ?

Around faucet handle is part of a(n) a. lever b. screw c. inclined plane d. wheel and axle

Carbon is allowed to diffuse through a steel plate 15 mm thick. the concentrations of carbon at the two faces are 0.65 and 0.30 kg c/m^3 fe, which are maintained constant. if the preexponential and activation energy are 6.2 x 10-7 m2 /s and 80,000 j/mol, respectively, compute the temperature at which the diffusion flux is 1.43 x 10^-9 kg/m^2 -s.

The combining of light nuclei is called blank. blank as in not actually blank. you know what im tryin to say.