15.
All of the following parameters are forces except

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

Determine the fraction of the magnitude of kinetic energy lost by a neutron (m1 = 1.01 u) when it collides head-on and elastically with a target particle at rest which is 21h (heavy hydrogen, m = 2.01 u).

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.