25. A bat strikes a ball into the outfield. If the action force is the bat hitting the ball, the reaction force is
A. the bat being dropped
B. the ball hitting the ground
C. the ball flying into the air
O
D. the ball hitting the bat

Use the profile illustrated for problem (1). assume that the layer of silty sand fill (sm) is placed over the entire site. estimate the thickness of the fill (h - in feet) that will cause the effective vertical stress at the center of the clay layer to increase by 517.5 pounds per square foot.