PLEASE HELP AND BE FRFR

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

You are assembling pieces of an iron gate to complete a fence. the finished gate will look like the one below. in order to assemble the gate it is important to under how the pieces are related. part 1: how are pies 1 and 2 in the archway related? part 2: how are the rectangular sections 5 and 6 in the center of the gate related to each other?

If g(x) = x+1/ x-2 and h (x) =4 - x , what is the value of ( g*h) (-3)?