Maria had a spool of ribbon 68 inches long. she cut the ribbon into 8 equal-length pieces. how long was each piece of ribbon? zach said the answer was 0.85 inches. is zach's answer reasonable? no

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