The star procyon, is actually a binary star system consisting of two stars, procyon a and procyon b. procyon a has a surface temperature of 6,500 k and a luminosity of 7.0 lsun. procyon b has a surface temperature of 7,700 k and a luminosity of 0.00050 lsun. what are the radii of the two components of procyon in units of rsun?

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.