Graph each equation by using the x-and y-intercepts x+y=4

What is the length of the midsegment of a trapezoid with bases of length 15 and 25 ?

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g

The answer is 7.2 how would you put this as money