Answer:

Step-by-step explanation:
Given


Required
Write the equation of the function 
Express the function as:

In: 

--- (1)
In 

--- (2)
Divide (2) by (1)






Substitute 5/6 for b in (1)






The function: 

The unit rate for 'y' is 1/8 per x .
The unit rate for 'x' is 8 per y .
I can’t really see what it says but it it’s total surface area it’s 9044.3 but it it’s lateral surface are it’s 7840
~Hello There!~
450/3 = 150
He would spend $150 each month
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