What force is responsible for the repulsion between two positively-charges particles?

Your pendulum clock which advances 1.0 s for every complete oscillation of the pendulum is running perfectly on earth at a site where the magnitude of the acceleration due to gravity is 9.80 m/s2. you send the clock to a location on the moon where the magnitude of the acceleration due to gravity is 1.65 m/s2.

Ineed the answer to question 1 , i’m desperate

Directions: count the number of atoms. ar co2 na3po4 so3 nac2h3o2