Answer no. 2 only. ASAP please

1. Two observers, A on Earth and Bin a spacecraft whose speed is 2.0 x 10\"3 m/s, both set their watches to the same time when the ship is abreast the Earth. (a) How much time must elapse by A's reckoning before the watches differ by 1.0 s? (b) To A, B's watch seems to run slow. To B, does A's watch seem to run fast, run slow, or keep the same time as his own watch? 2. An astronaut whose height on the Earth is exactly 6.0 ft is lying parallel to the axis of a spacecraft moving at 0.9 c relative to the Earth. (a) What is his height as measured bv an observer in the spacecraft? (b) By an observer on the Earth? 3. The mass of a particle is triple its rest mass. What is its speed? 4. What is the Kinetic Energy (in MeV) of a neutron whose mass is double its rest mass