alod Jocko orit vo aswollewe zi brs aosnad save or 9. (8 points total) When a Sun-like star starts to ascend the red giant branch, its luminosity changes. The new luminosity can be approximated by the equation L = the where Lo and Mo are the Sun's luminosity and mass, and Mcore is the mass of the helium core at the center of the evolved star. As hydrogen is fused into helium and added to the core, efficiency of the conversion between mass and energy is given by AE 0.007 AMcorec. In this case, we can write a simple differential equation in time for the mass of the helium core: = in uns L= = 105 LO McCore MO AE DE 0.007AMcorec At dt At (eining C) oelpolso x = 0.007c dMcore) (ame dt = moo (d) he 102 101 105 Lo MO (Moore) (d) (a) By rearranging the variables in the last two terms of the above equation and performing a pair of simple integrations, solve the above equation to obtain an expression for how the mass of the core changes with time, in terms of Lo, Mo, c, t, and the initial and final core masses Mc