Why is a volumetric pipette more precise than a measuring cylinder?

Volume of liquids are measured in experiments. The volume is measured by taking reading that coincides with the lower meniscus of the liquid. There are several measuring devices used in laboratory such as beakers, measuring cylinders,  volumetric pipets etc. volume measured from volumetric pipets are considered to be more precise than from measuring cylinders because they are simple, and its long neck lowers the chances of error in looking for the meniscus.

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.