The magnitude of an electric field balancing a deutron of charge 1.6 x 10^-19 C and mass 3.2 x 10^-27 kg is:

The magnitude of the charge of a single electron or a proton is $1.6\times {10}^{-19}C$.
What is the net charge of an object that has 20 electrons and 22 protons?

A silk cloth rubbed with a glass rod acquire a charge (-1.6 - 10 ^-19) C. Then the charge on the glass rod is