Help pls I'm running out of points & brain cells lol T^T

Write the pair of fractions as a pair of fractions with a common denominator

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

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?