<span>3(7 + 4)2 − 14 ÷ 7
First do the parenthesis
7 + 4 = 11
so the question looks like: 3(11)2 - 14/7
Then multiply 3, 11, and 2 together
3 x 11 x 2 = 66
66 - 14/7
14/7 equals to 2
66 - 2
Then just simplify
66 - 2 = 64
64 is your answer
hope this helps</span>
Answer: 
Step-by-step explanation:
(a) Given
Sam charge $5 for each dog for a thirty minute walk
For an hour which is double the thirty minutes, it must be double of the same charge.

(b)Given
With $20, Christie sells 100 cups of lemonade with a quarter per cup charge
For 100 cup, she generate a revenue of

So, she earns
that is , her profit is 
This is a simple consequence of the Zero-sum problem: https://en.wikipedia.org/wiki/Zero-sum_problem
Answer:
Step-by-step explanation:
x= 1/4