This doesn't represent an function. Because the output is uneven to the other outputs,
1=4, 2=7 if you divided 2 into 2 parts it would equal 1=3.5 not 4.
You're right.
Since the output has different number of jumps from one number to another.
Answer:
$30
Step-by-step explanation:
Multiply $7.50 by 4 (Him and his friends) and you get a sum of $30
Each of them have 2.50 left