A. for the circumference it is C=pi(d)=pi(2r)=pi(10)= 31.4 ft
b. for the area it is A=pi(r)^2=pi(5)^2=pi(25)= 78.5 ft squared
c. since the are is 78.5 ft squared multiply by $4.50= $353.25 to floor the circle.
The hint says that volume of a rectangular solid = l*w*h, where l = length, w = width, and h = height. Use this to solve for the height of the solid by plugging in the numbers you know.
You know that length, l = 2cm, width, w = 8cm, and, *EDITED* volume = 160 cm^3. Plug these values into the equation for volume (the hint) and solve for h, the height:
Volume = lwh
160 = (2)(8)(h)
160 = 16h
h = 10cm
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Answer: The height is 10 cm
45 + 2 × [ (45 × 60) + 25]
45 + 2 × 2700 + 25
70 + 5400
5470