How many black keys would you expect to find on a keyboard with 72 keys in all? Show your work. I need this ASAP.

Will pick brainliest.

Select all the correct statements. the amount in dollars an electrician charges in terms of the number of hours worked is represented by the function y = 22x + 42. from the function, identify all the phrases that hold true for the situation. the electrician charges an initial fee of $22 the y-variable represents the number of hours the electrician charges an initial fee of $42 the electrician charges $22 for every hour worked the x-variable represents the electricians charges in dollars the electrician charges $42 for every hour worked

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.

The administrator of a large assisted living facility wanted to know the average age of the residents living at the facility. he randomly selected 12 residents and determined their age, listed here: 80, 65, 75, 83, 68, 73, 88, 79, 94, 72, 79, 68 what's the average age of the sample of residents? a. 79 years old b. 68 years old c. 75 years old d. 77 years old