A lot of physics questions, please I really need help answering them

Question

Jupiter has a mass of 1.90 x 10²⁷ kg. the semi-major axis of its orbit is 7.78 x 10¹¹. Th radius of the planet is 7.14 x 10⁷ m. 

• Io, one of jupiter's moons, orbits at a distance of 4.22 x 10⁸ m. If Jupiter attracts Io with a force of 4.90 x 10²¹ N, what is Io's mass?
• if Io completes one orbit of Jupiter in 1.53 x 10⁵ s, what is K for jupiter's moons? 
• Ganymede, another of Jupiter's moons, orbits at a distance of 1.07 x 10⁹ m. What is its period? 
• What is the acceleration due to jupiter's gravity at jupiter's surface?
• jupiter's closest approach to the earth is 5.90 x 10¹¹ m away. At this distance, what force does Jupiter exert on the earth? 
  
• When Jupiter is closest to the earth, what is the acceleration of the earth due to jupiter's gravity? 
• When Jupiter is closest to the earth, what force does it exert on a 55.0 - kg person? 

 

Im sorry sorry for the long question guys but please help I really need these questions answered, just try to answer at least some of them THANKS 

Answer 1

F = G*(mass of Jupiter)*(mass of Io)/(distance of orbit)²

 

so

 

mass of Io = F*(distance of orbit)² / (G*(mass of Jupiter))

                = (4.90*10²¹ N)*(4.22*10⁸ m)² / ((6.67*10^-11 N m² / kg²)*(1.90*10²⁷ kg))