This, Im stuck, please help

What is the measure of angle z in this figure? enter your answer in the box. z = ° two intersection lines. all four angles formed by the intersecting lines are labeled. clockwise, the angles are labeled 43 degrees, x degrees, y degrees, and z degrees.

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

What is the effect on the graph of the function f(x) = x2 when f(x) is changed to f(x) − 4?