Solve the question pls

Ameteorologist is studying the monthly rainfall in a section of the brazilian rainforest. she recorded the monthly rainfall, in inches, for last year. they were: 10.4, 10.3, 11.7, 11.1, 8.0, 4.4, 2.6, 1.8, 2.5, 4.4, 7.3, 9.5 fill in the missing values in the formula. what is the variance?

Amayoral candidate would like to know her residents’ views on a public open space before the mayoral debates. she asks only the people in her office. her co-workers are an example of a census population convenience sample simple random sample

If there are 825 students at cherry hill high school and 4 out of every 5 students voted in the student council election, how many students voted?