1. When a rubbed ruler is brought close to the paper, salt and pepper they are not equally attracted as paper is lighter than pepper and salt, so it takes less effort for paper to overcome the force of gravity.
2. electrostatic induction is a phenomenon in which static electricity is generated in an object by bringing an electrically charged object near it. When a charged object is brought near to an uncharged body it causes electrical charges to redistribute in the body, resulting one side having excess of positive charges and other side having negative charges, as a result body become charged. Electrostatic interaction also depends upon the nature and mass of body.
b. the combination of fur cloth and rubbed ruler produce greatest effect. The reason is that when ruler is brought near to fur excess of electron will flow into fur.
Organisms from the same genus must have features that can make them part of a same group like anatomic features, however if the organisms cannot produce fertile offspring if they interbred each other they are not from the same species.