Radiation from the sun reaching earth (just outside the atmosphere) has an intensity of 1.43 kw/m2. (a) assuming that earth (and its atmosphere) behaves like a flat disk perpendicular to the sun's rays and that all the incident energy is absorbed, calculate the force on earth due to radiation pressure. (b) for comparison, calculate the force due to the sun's gravitational attraction. assume that the speed of light and earth radius are 2.998 × 108 m/s and 6.37 thousand km respectively.