You write it as 0.5. Just divide both numbers
1 : the perimeter of a circle The circle measures 22 inches in circumference. 2 : the external boundary or surface of a figure or object : periphery from the center to the circumference of the sphere.
32 if you fold it 4 times and times that by 2 it will be 32
So, the function is obviously shifted up by 1 so it rules out A and B, and we also see that the period is 4pi rather than 2pi, and using the fact that:

Now that we know our b value, we see that the correct answer would be C.
Harrison is correct because the 305 in the actual problem is greater than the 300 in the estimate and 57872 is less than 60000. Harrison arrived at his prediction by rounding to the nearest ten thousand and nearest hundred.