Jan needed to empty 18 gallons of water from a tub into jugs that hold 0.5 gallons of water. how many jugs did jan need?

Total quantity of water that Jan needed to empty = 18 gallons
There are other important information's already given in the question. Based on those information's the answer can be easily deduced. 
Number of jugs that can hold 0.5 gallons of water = 1
Then
Number of jugs required to hold 18 gallons of water = 18/0.5
                                                                                   = 36
So 36 jugs are required by Jan to empty 18 gallons of water.

Okay so for every triangle has three angles that always add up to 180 degrees. and to tell the difference between whether they are secure, right or obtuse is that acute: has one angle that is less than 90 degrees. right triangle means there is at least one angle that is exactly 90 degrees. and an obtuse angle has an angle that is bigger than 180 degrees. i’ll do #13 as an example: 13. 40 and 50 so if every triangle has 180 degrees 40+50= 90 degrees then180-90= 90 degrees so the third angle is 90 degrees and because this triangle has a 90 degree angle it means it is a right triangle