This is not a solution. When plugged in,
8 > 20 + 4.
8 > 24, which is not true. :)
Answer: The answer is 314.28 cm² (approx.).
Step-by-step explanation: Given that an engineer is going to install a new water pipe. The diameter of this circular pipe is, d = 20 cm.
We need to find the area 'A' of the circular cross-section of the pipe.
Given, diameter of the circular section is

So, the radius of the circular cross-section will be

Therefore, cross-sectional area of the pipe is

Thus, the answer is 314.28 cm² (approx.).
Answer:
D
Step-by-step explanation: