the answer to a word problem should always include what?

Question

a. decimals

b. exponents

c. units

d. variables

Answer 1

I agree with Kenneth.  Without units, a number is meaningless and serves no purpose.

Answer 2

the units--that is, temperature can be 16 deg Celsius or 61 deg Fahrenheit; lengths can be inches, meters, lightyears, etc., so what the system of metrics is is just as important as the plain number.