Matthew drops a ball and watches it bounce back up from the ground. he draws a force diagram that shows the forces when the ball collides with the ground. which diagram correctly shows the forces involved?

Asynthetic fiber used in manufacturing carpet has tensile strength that is normally distributed with mean 75.5 psi and standard deviation 3.5 psi. how is the standard deviation of the sample mean changed when the sample size is increased from n equals 8 to n equals 47