An astronaut requires 2.3 lb of oxygen per day while in space. how many pounds of oxygen are needed for a team of 4 astronauts for 7 days in space?

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.

Which of the following is not a subset of {1,2,3}?

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.