PLEASE HELP ME WITH THIS ONE QUESTION You have 1 kg of water and you want to use that to melt 0.1 kg of ice. What is the minimum temperature necessary in the water, to just barely melt all of the ice? (Lf = 3.33 x 105 J/kg, cwater 4186 J/kg°C)

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?