Yolanda saves money to buya $200 cell phone. she has $70, and saves $25 each week. write and solve an inequality to find out how many full weeks yolanda must save to have at least enough to buy the cell phone.

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