The reasons that the sample is representative:
The builders were chosen at random
The population included only builders who build in Vicki's town
Vickie wanted to determine the cost of building a house in her home, so the fact that the builders were from her town makes the sample more representative. Moreover, the random choosing of the builders helps to remove any biases that may be present.
2 adults costs $31.50, one child costs $8.25, add these together and you will get $39.75
Whenever you face the problem that deals with maxima or minima you should keep in mind that minima/maxima of a function is always a point where it's derivative is equal to zero.
To solve your problem we first need to find an equation of net benefits. Net benefits are expressed as a difference between total benefits and total cost. We can denote this function with B(y).
B(y)=b-c
B(y)=100y-18y²
Now that we have a net benefits function we need find it's derivate with respect to y.

Now we must find at which point this function is equal to zero.
0=100-36y
36y=100
y=2.8
Now that we know at which point our function reaches maxima we just plug that number back into our equation for net benefits and we get our answer.
B(2.8)=100(2.8)-18(2.8)²=138.88≈139.
One thing that always helps is to have your function graphed. It will give you a good insight into how your function behaves and allow you to identify minima/maxima points.
Answer:
y + 2 =
(x - 1)
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
y - 4 =
(x - 3) ← is in point- slope form
with slope m = 
Parallel lines have equal slopes, thus equation of parallel line
with m =
and (a, b) = Q(1, - 2) is
y - (- 2) =
(x - 1) , that is
y + 2 =
(x - 1)
I'm pretty sure the answer is 2.9 because It's closer to 3 than 2