What will be the circumference of 25mm pipe?

To calculate the circumference of a pipe, you can use the formula ( C = \pi \times d ), where ( d ) is the diameter. For a 25 mm pipe, the diameter is 25 mm. Therefore, the circumference is approximately ( C = \pi \times 25 \approx 78.54 ) mm, using ( \pi \approx 3.14 ).