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 
If a shape is a square, this mean that each side has the same length. This means that each side of the square has a length of 17cm. Perimeter is the length of the outer boundary of a shape or the summation (addition) of all the sides. This means that the perimeter of this square is 17+17+17+17 or 17×4 which is equal to 68cm.
I hope this helps!
Given:
The function, f(x) = -2x^2 + x + 5
Quadratic equation: 0 = -2x^2 + x +5
where a = -2
b = 1
c = 5
The discriminate b^2 - 4ac = 41
To solve for the zeros of the quadratic function, use this formula:
x = ( -b +-√ (b^2 - 4ac) ) / 2a
x = ( 1 + √41 ) / 4 or 1.85
x = ( 1 - √41 ) / 4 or -1.35
Therefore, the zeros of the quadratic equation are 1.85 and -1.35.
