Question

The radius of a circle increases at the rate of 2 cm per second. Find the rate at which its area and circumference increase at the instant when the radius is 7cm. ​

Answer 1

Answer:

ok The circumference of a circle is 2πr or πD if diameter is given.

The answer is 25.13 cm

Step-by-step explanation:

Now method 1:

C=2πr

So finding for radius in this equation=diameter/2

8/2=4 cm

So now 2 × 22/7 × 4

176/7=25.13 cm

OR

C=πD

22/7 × 8

176/7=25.13 cm

Answer 2

Answer:

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