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7/2 pi

or approximately 10.99557429

Step-by-step explanation:

2 pi sqrt( a/b)

let a = 49 and b = 16

2 pi sqrt( 49/16)

We know that sqrt( a/b) = sqrt(a) /sqrt(b)

2 pi sqrt(49) / sqrt(16)

2pi ( 7) / (16)

2 pi ( 7/4)

7/2 pi

This is the exact answer

We can make an approximation for pi

Using the pi button on the calculator

10.99557429

it's d

step-by-step explanation: