Flow Control – Mislabeled???

How does a flow control control flow since all the oil in equals all the oil out?

Vertical Cylinder Question

Single Rod Cylinder – vertically mounted with rod up
10″ Bore, 4″ Rod, 10″ stroke
Cap is vented to atmosphere and Rod end is plugged; assume no leakage.
Cylinder is about 3/4 extended.
What happens when a 500 lb load is applied to the rod?