1what properties of a star are needed to calculate the star's luminosity? a. size and apparent brightness b. mass and distance to the star. c. temperature and diameter of the star d. apparent brightness and distance to the star. 2.which cool and bright stars are located in the upper right of the h-r diagram? a. red giants b. neutron stars c. white dwarfsd. main sequence

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.