Can someone please help :( Ignore the answer I clicked

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

Which basic geometric term has no width, no length, and no thickness? line b. point c. angle d. plane

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?