Can someone really help me please!!

Ablock of wood is a cube whose side is x in. long. you cut off a 1-inch thick piece from the entire right side. then you cut off a 3-inch thick piece from the entire top of the remaining shape. the volume of the remaining block is 2,002 in3. what are the dimensions of the original block of wood?

In the equation sqrt(n+5)-sqrt(11-10)=1. what is the value of n

Which statement best describes how to determine whether f(x) = x squared- x +8 is an even function ?