PLEASE HURRY What is the wavelength of light with 2.89 x 10-19 J of energy? (The speed of
light in a vacuum is 3.00 x 108 m/s, and Planck's constant is 6.626 x 10-34
Jos.)
A. 764 nm
B. 1310 nm
C. 1450 nm
D. 688 nm

how important do you think an instrument is to the musician who plays it?

it is the minimum amount of material needed to sustain a fission reaction.

critical mass is the minimum amount of fissionable material that must be assembled for a sustained fission reaction to take place. although two to three neutrons are produced for every fission, not all of these neutrons are available for continuing the fission reaction. if the conditions are such that the neutrons are lost at a faster rate than they are formed by fission, the chain reaction will not be self-sustaining.   at the point where the chain reaction can become self-sustaining, this is referred to as critical mass.