The number of visible stars in the night sky, , can be estimated by the formula
where
is the number of stars counted through a tube with length
, in centimeters, and a circular mouth of area
, in square centimeters. Based on the formula, what is the estimated number of visible stars in the night sky if 240 stars are observed through a tube 10 feet long with a mouth of radius of 4 feet? (1 foot = 30.48 centimeters)