Volume Questions

When selecting the volume for a block, lets say 100 reps/muscle group is choosen. When training the lower body in one day does this mean 100 reps for quads, 100 reps for hams or 100 reps for quads/hams?

A)If choosing 2 weekly workouts per muscle group would that mean 100 reps on quad dom day and 100 reps on hip dom day or 50 reps on each day?

B)If spilting upper body into one day of vertical movements one day of horizontal movements would this be considered trainig a muscle group 2x per week (since the back is trained each day) or 1x pre week(since chest is trained only once)?

C)Is this way of selecting volume appropriate for athletes?

Bump??