Need help on both of these questions pls

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Two planes leave an airport at the same time, one flying east, the other flying west. the eastbound plane travels 20 mph slower. they are 1600 mi apart after 2 hr. find the speed of each plane.

What set does not contain -3 the set of all real numbers the set of all integers the set of all whole numbers the set of all rational numbers