Anumber cube is rolled. what is p(3 or an even number)? a)1/2 b)2/3 c)4/2 d)1/6

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