Answer:
Only C is a function
Step-by-step explanation:
To test whether a graph is a function you use the vertical line test.
If you can place a vertical line anywhere on the plane (in the domain of the "function" to be tested) and it intersects the curve at more than one point, the curve is not a function.
We see with A, wherever we put the vertical line it intersects twice.
With B, it intersects infinitely many times.
C is a function because wherever we put the vertical line, it only intersects once.
D is a function because it intersects twice providing we do not put it on the "tip" of the parabola.
The mathematical reasoning behind this is that a function must be well-defined, that is it must send every x-value to one specific y-value. There can be no confusion about where the function's input is going. If you look at graph B and I ask you what is f(3)? Is it 1? 2? 3? ... Who knows, it's not well-defined and so it's not a function. However if I ask you about C, whichever input value for x I give you, you can tell me to which y-value it gets mapped/sent to.
x = perimeter
x<156
length = 66
so, in order to calculate perimeter you need to add two lengths and two widths
so
156 (perimeter) - 2 (66) = two widths
156 - 132 = 24 (remember this number is two widths added together)
so 24 twice the width SO 12 would be the number that the width can't be larger than
the width has to be less than 12
w < 12
Answer:
Step-by-step explanation:
a) H0: 
Ha: 
(Two tailed test at 5% significance level)
b) n=30
Mean difference = 
Std error of mean = 
b) Test statistic t = mean diff/std error = -1.552
df = 30-1 =29
p value=0.0657
c) Since p > 0.05 our signi. level, we accept null hypothesis.
There is no significant difference between the means.
d) Using critical value we find that test statistic is > critical value left
So accept H0