Answer:
1.10^6 kg of mass per second
Step-by-step explanation:
All energy lost by the sun comes from nuclear fusion.
Sun loses energy at 2.5*10^{19}J per hour, that is 9*10^{22}J/s
To find the mass lost by the sun in liberation of energy you use the famous Einstein's equation:

hence, the sun liberates 1.10^6 kg of mass per second