Can anyone help me with this ASAP please?

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

Graph y ≥ -x^2 - 1. click on the graph until the correct graph appears.

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.