I have 5 questions that i need hep with.

The mean average cost of standard room per night at a hostel is ? 20.60. therefore, how much does a standard room cost per night at night-time rest days?

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?

Recall that two angles are complementary if the sum of their measures is? 90°. find the measures of two complementary angles if one angle is twenty dash nine times the other angle.