Help me solve this problem, I am lost here.

Question

These are integers,

15-12-8=

also 4-(-7)-9=

and -11-(-5)-(-6)=

Answer 1

15-12=3
3-8=-5

4-(-7)=4+7=11
11-9=2

-11-(-5)=-11+5=-6
-6-(-6)=-6+6=0

Answer 2

create a set of data showing temp. highs for ten days that satisfies these conditions mean-72 median-74 mode-68 range-21