The accounting concepts are business entity, going concern, historical cost, conservatism, consistency etc.
Answer:
34
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is

Here [ a, b ] = [ 1, 6 ], thus
f(b) = f(6) = 6³ - 9(6) = 216 - 54 = 162
f(a) = f(1) = 1³ - 9(1) = 1 - 9 = - 8
average rate of change =
=
= 34
8th payment, if you want how to get the answer I made a chart as shown in the picture
50 x 3.14 = 157 i think this is the answer