19. Stephen can deliver 20 papers in 2 hours. Which of the following units could represent the rate at which Stephen can deliver pap
А.
papers x hour
B
papers x 2 hours
С
papers
hour
D
papers
2 hours

Im literally having a mental breakdown

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%

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