A sideways opening parabola is in the form

, so we know from the process of elimination that it will either be b or c. Next we have to realize that if the parabola opens to the left it is a negative parabola, just like if a parabola opens upside down it is a negative parabola. So the one that has the negative out front is b.
23,039.
y=13,000(1.045)^t
t=13
You get 1.045 because you add 1+ the percentage in decimal form.
Answer:
The standard deviation is 10.38
Step-by-step explanation:
Given;
Variance, v = 107.76
mean, x = 34.2
The standard deviation is given by;
standard deviation = √variance
standard deviation = √107.76
standard deviation = 10.381
standard deviation = 10.38 (two decimal places)
Therefore, the standard deviation is 10.38