Answer:
B. 88.5
Step-by-step explanation:
first we add all the numbers :
(79 +80 +92 +92 +81 +100 +88 +98 +71 + 100+91+90) over 12
= 1062 over 12
= 88.5
[why over 12? because there's 12 numbers]
Answer:
15,17,19
Step-by-step explanation:
Make an equation : 
Solve the equation:



Since x=15 then the second number is 17 and then 19
Hope this helps!
Stay Safe
Answer:30
Step-by-step explanation: