Finishing missing angles. What does x equal?

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

What is the solution to the equation? k/6.4=8.7 2.3 5.568 15.1 55.68

Identify all the cases where non-probability sampling is used when attempting to study the characteristics of a large city. studies on every subject in the population divide a population in groups and obtain a sample studies with a limited amount of time demonstrate existing traits in a population studies with the nth person selected