Write the correct answer.
The Beaufort Scale is used to measure
the intensity of tornados. For a tornado
with Beaufort number B, the formula
v = 1.9 B raised to ( 3/2) may be used to estimate the
tornado's wind speed in miles per hour.
Estimate the wind speed of a tornado
with Beaufort number 9.
a) $39.9$ mph
b) $57.3$ mph
c) $69.8$ mph
d) $75.6$ mph