Please solve it quickly please

(K:2, A:2) Question 1: Two equal masses sphere, one has + 15pC and the other has +24pC are separated by 25 cm horizontally. A. Determine the electrostatic force between the two spheres. B. Determine the masses if the gravitational force between the two spheres have the same magnitude as the electrostatic force. (A:2, C:2) Question 4: A solenoid shown below, has a total of 200 turns with current of 3.0 A pass through the wire. Indicate the poles on this solenoid and then calculate the magnetic field strength of this solenoid. (1:6, A:2) Problem 1: An international space station (ISS) with mass of 1.6* 10* kg and radius of 2.50 km is located at a height of 1,250 km above the Earth surface. A. Find the orbital speed and the period of this space station at this location. (1:3) B. What would be the period of this space station if a person would like to experience an Earth-like gravity (i.e. g - 9.8 m/s )? (A:2)