Suppose a laboratory has a 38 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 ; 0.07 g
8 ; 2,2622 g
8 ; 4.75 g
8 ; 0.15 g

Agraphic designer created a logo on eight and a half by 11 inch paper. in order to be placed on a business card, the logo needs to be one and 7/10 inches by 2 and 1/5 in. what is the scale factor of the dilation

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

Taber invested money in an account where interest is compounded every year.he made no withdrawals or deposits. the function a(t)=525(1+0.05)^t represent the amount of money in the account after t years. how much money did taber origanally invested?