Why is a normal eye not able to see clearly the object placed closer than 25 cm?

Find the volume of the ellipsoid x^2+y^2+5z^2=36.

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.

Multiply or divide to make this english distance conversion. 174 inches = feet (14.5, 58, 2,088, 23)