how many questions is the cumulative exam on edge??( i have no clue where to put this question so math it is-)

Which of the following transformations will always produce a congruent figure?

You dug a hole that was 8 feet deep. after taking a short break, you dug down 3 more feet in the same hole. when finished digging, a tractor accidentally filled the hole with 4 feet of dirt. how deep is your hole now?

The volume of the a sphere whoes diameter is 18 cm is cubic cm . if it's diameter were reduced by half, it's volume would be of its original volume