This depends on the coach or team's strategy. Blocks are mostly used when an opposing team member, such as an outside hitter, goes to hit. Some teams attempt to block back row attacks and free balls too, but this varies.
block the ball from crossing to your side of the court
A block in volleyball is when you jump up straight with you hands straight and you block a spike.
3. 4 if there is a block
only 5 players play
serve, pass, set, hit, block
Yes, the libero can set. However the libero may not block, attempt to block, or serve.