a.[2]
A construction worker uses a heavy-duty steel pry bar to lift a heavy concrete slab.
Explain why the downward effort force needed to lift the concrete slab is less than the upward load force acting on the slab.
b.[2]
The effort force applied by the worker is 140 N140\text{ N}140 N.
Calculate the load force exerted on the concrete slab.
c.[2]
A technician places a heavy car battery on a flat horizontal workbench.
Describe the two forces in the interaction (action-reaction) pair between the battery and the workbench.
d.[2]
Describe the forces acting on the battery that would appear in its free-body diagram, specifying their names, directions, and relative magnitudes.