How do you get the value of the expression

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.

Yvaries inversely as x. y =12 when x=5. find y when x=4

The high temp today was 62°. when nighttime comes, the temp will drop 40°. by 4am the temp will drop an additional 40°. what is the temp at 4am?