When did the ball fly farther—when it hit the moving bat or the bat that did not move?

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

In positive numbers less than 1, the zeros between the decimal point and non zero are significant

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.