Answer:
5
Step-by-step explanation:
Change 6 1/4 into an improper fraction
6 1/4 = (4*6 +1)/4 = 25/4
Multiply by the fraction
25/4 * 4/5
5
There are 5 gallons left
Answer: b. 6(x + 4)
Step-by-step explanation:
The given word phrase = the product 4 more than x and 6
where , 4 more than x is equivalent to 
Therefore the algebraic expression for the given word phase "the product 4 more than x and 6"
=

Hence b. is the right option.
The algebraic expression for the given word phase is 
If it costs 3n+5, you have to plug 7 in for n and solve. 3(7)+5=26 so $26