Solve the following system of equations using substitution:
2x - 2y + z = 8
-y+z=4
2z=4

What is the missing step in this proof ?

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent ?

In a certain city, the hourly wage of workers on temporary employment contracts is normally distributed. the mean is $15 and the standard deviation is $3. what percentage of temporary workers earn less than $12 per hour? a. 6% b. 16% c. 26% d. 36%