The function will be

where y is the balance, and x is the number of month.
The raph will be a line on the xy-plain which starts at the point (0, 360), and end in the point (72, 0).
Hope it helps.
-5 is for f(x)=x+5
4 is for g(x)=x-4
Hope this helps!!
It would be a linear function
Tautology is when something is repeated in a sentence but using different words. It can be used to enrich the sentence but also it can be needless repetition.
5 statements that would produce a tautology:
1. Lets order a toast sandwich.
2. In my opinion, I think he is right.
3. The Gobi is a very dry desert.
4. The hurricane hit in 3 p.m. in the afternoon.
5. Don't worry, everything is well and good.
The towns would be 380 km apart. You find this by multiplying the scale accordingly (in this case 5*76)