The answer is B.
The attached file is how I got the answer.
Hope this helped :)
The answer is 90
to find the median of a number is to just find the middle number if you were to put them in order from least to highest
also, there are mean, median, mode calculators that u can use online
Let m be the slope:
m=(y₂-y₁)/(x₂-x₁)
solve for c:
1/6=(9-c)/(1-7)
1/6=(9-c)/-6
-1=9-c
-10=-c
c=10