Give a specific example of a machine, and describe how its mechanical efficiency might be calculated

Abaseball is thrown from the outfield toward the catcher. when the ball reaches its highest point, which statement is true? (a)its velocity is not zero, but its acceleration is zero. (b) its velocity and its acceleration are both zero. (c) its velocity is perpendicular to its acceleration. (d) its acceleration depends on the angle at which the ball was thrown. (e) none of the above statements are true.

How can you measure the amplitude of a longitudinal wave?

Select the correct lewis structure for fluorine which is group 7a element?