The average January surface water temperatures (°C) of Lake Michigan from 2000 to 2009 were 5.07, 3.57, 5.32, 3.19, 3.49, 4.25, 4.76, 5.19, 3.94, and 4.34. The mean value of these temperatures is 4.312. What is the variance of this data set?

Candice uses the function f(t)=t+100−−−−−−√ to model the number of students in her after-school program. the variable t represents days and f(t) represents the number of students. how many days does it take for there to be 15 students in her program? a. 225 days b. 125 days c. 325 days d. 115 days