Please help me i dont understand

If you roll two fair dice (one black die and one white die), in how many ways can you obtain a 4 on at least one die?

In right ∆abc shown below, the midpoint of hypotenuse ac is located at d and segment bd is drawn. if ab = 12 and bc = 16, then explain why bd = 10. hint: consider what you know about the diagonals of a rectangle.

35 ! insert < , > , or = to make the sentence true. 12 __ 25 > =