State if it is acute obtuse or right

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.

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

Given: circle o, cd is diameter, chord ab || cd. arc ab = 74°, find arc ca.