Whats the area? how do i find it? in these specific questions?

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Polygon abcde is reflected to produce polygon a′b′c′d′e′. what is the equation for the line of reflection?

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?