Please help I’ll mark brainliest

What is the distance between the points (2 -3) and (-6 4) on the coordinate plane

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

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?