If the number of bacteria in a colony doubles every 85 hours and there is currently a
population of 500 bacteria, what will the population be 170 hours from now?
bacteria

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

3.17 scores on stats final. below are final exam scores of 20 introductory statistics students. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 57, 66, 69, 71, 72, 73, 74, 77, 78, 78, 79, 79, 81, 81, 82, 83, 83, 88, 89, 94 (a) the mean score is 77.7 points. with a standard deviation of 8.44 points. use this information to determine if the scores approximately follow the 68-95-99.7% rule. (b) do these data appear to follow a normal distribution? explain your reasoning using the graphs provided below.

X+y=-4 x-y=2 use elimination with adding and subtraction