5.8/ sqrt 80=0.648 I think you are asking for the standard margin
Hope this works
Answer: $156.86
Step by Step:
136.40 x .15 = 20.46
136.40 + 20.46 = 156.86
The length of that arc is (90/360)·2·π·6 = (1/4)·12·π = 3·π ≈ 9.42 units;
Because there are only two things you can do with these two " family" members. 81 divided by 9 is 9. 9 times 9 is 81. Strictly speaking, there should be three in the family: 9,9 and 81 9 is the square root of 81. 81 is the 9 squared.
Answer: 14x - 42
Hope this helps!