If the magnetic field is weak how is the magnetic force affected

If the magnetic field is weak, the magnetic force must either be weak as well, unless the particle is very strongly charged, or the particle is moving very fast (or both)

Hope this helps

a polar bond is formed when electrons are shared unevenly between atoms

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.