answer the following physics questions. just the answer would be fine.

1. Calculate the value of the gravitational eld strength g, 250 km above the surface of Earth. {rE = 6.38 x 10"' m, ME = 5.98 x 10'24 kg) 2. The lntemational Space Station is in orbit about 420 km above the surface of Earth. Calculate how many minutes it would take for the ISS to complete one orbit. {rE = 6.38 x 10% m, ME = 5.98 x 10"'24 kg] 3. How much work is done against gravity to move a ?20 kg weather monitor 120 km into the air? (rE = 6.33 x 10*6 m, ME = 5.93 x 10"'24 kg) 4. List TWO differences between charging an object by contact and charging an object by friction 5. Two equal charges of magnitude 1.1 x 10t-TC experience an electrostatic force of 4.2 x 10\"4N. How far apart are the centres of the two charges? 6. Calculate the electric eld 1.0 m from a small sphere with a positive charge of 3.2 x 10h3C. Describe the direction as outwards or inwards. T'. A uniform electric eld has a strength of 120 NIB. An alpha particle with a charge +2e is pushed against the eld direction by an external force for a distance of 25 cm. How much electric potential energy does the alpha particle gain? 8. In a Millikan-type experiment. two horizontal parallel plates are 1.0 cm apart. A sphere of mass 2.2x1-13 kg remains stationary when the potential difference between the plates is 350 V with the upper plate negative. a) Is the sphere positively or negatively charged