What is the answer to the letter u?

Campus rentals rents 2 and 3 bedrooms apartments for $700 ans $900 a month respectively. last month they had six vacant apartments and reported $4600 in lost rent. how many of each type of apartment were vacant?

An airplane travels at an unknown elevation before it descends 3 miles to an elevation of 15 miles. find the elevation of the plane before its descen.

∠1 and ∠2 are vertical angles. ∠2 has a measure of 63°. what is the measure of ∠1 ? enter your answer in the box.