Exact Surface Area = 378pi
Approximate Surface Area = 1186.92
The approximate surface area uses pi = 3.14
The units are cm^2 or "square cm".
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Work Shown:
SA = surface area of cylinder
SA = 2*pi*r^2 + 2*pi*r*h
SA = 2*pi*7^2 + 2*pi*7*20
SA = 2*pi*49 + 2*pi*140
SA = 2*49*pi + 2*140*pi
SA = 98pi + 280pi
SA = 378pi ..... exact surface area
SA = 378*3.14
SA = 1186.92 ..... approximate surface area
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Side note: The diameter 14 cuts in half to get the radius r = 7
Answer: 283
Step-by-step explanation:
To do this, it is helpful to get an equation you can use to solve any term.
This equation is:

So simply plug in 31 for n to get



Answer:
He spends $298
Step-by-step explanation:
He has 16 curtains
16*2=32
That answer is how many he needs
Now multiply that by the price
32 curtains for $29
32*29=928
The answer is $928
Radius is 3 And diameter 3×2