It is snowing where Jenna lives. It's been snowing all day, but now the snow has changed to sleet and then to freezing rain. What is happening to cause these changes?

The snow went through different pockets of temperature throughout the day.

Explanation:

Snow forms when the temperature of the atmosphere is at 32 degrees Fahrenheit or below, while it is raining.

When this snow changed to sleet, all that happened was the snow warmed a bit while falling, causing it to melt a little. After this, it then went through a pocket of cold air before reaching the ground, causing it to refreeze, which in result, is sleet.

Freezing rain is quite similar to sleet in terms of changing temperature. In this case, snow hits a large warm pocket of air, causing it to melt more than (snow turning to sleet), making it melt completely, and turning back to rain. This rain then hits a small pocket of cold air right before reaching the ground, but not a large enough pocket to turn to sleet. In result, you get freezing rain.

idk what the question is about

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.