the ratio of refillable bottles to disposable bottles is 7:3 if there's 21 refillables bottles how many disposable bottles are there

What is the exact volume of the cylinder? 16in going into the middle of the top of the cylinder and 40in in height a) 25,600(pi)3 b)10,240(pi)3 c)1280(pi)3 d)640(pi)3

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

Marlow is comparing the prices of two trucks rental compaines company a charges $3 per hour and an addtional $75 as serivce charges company b charges $2 per hour and an additional $85 as serivce charges