You are comparing a reaction that produce a chemical change and one that produce a phyical change

Apopulation of bolts has a mean thickness of 20 millimeters, with a population standard deviation of .01 millimeters. give, in millimeters, a minimum and a maximum thickness that includes 68% of the population of bolts.

The author believes that the concept of fairness is not a useful term

Ateacher attaches a ball to a meter long string and whirls it around in a horizontal circle at constant speed. the teacher explains that the string is what makes the ball go in a circle. why is the string necessary? a) the string is needed to apply a torque to the ball. b) the string is needed to push on the ball to get it up to speed. c) circle motion requires an inertia which is provided by the string. d) circle motion requires a force to give it a centripetal acceleratio