Given that radius of orbit of earth and Mars is m and m respectively . [1 year= s , radius of sun = , mass of helium atom= kg ]

Determine

(1) Period of revolution of Mars

I found this to be 1.9 year .

(2) Mass of sun

i am not sure bout this

(3) Escape velocity of helium atom from the surface of the sun

i tried using this formula

Where M is the mass of sun and r is the radius of sun and of course G is the gravitation constant .