Answer:
The degrees of freedom are given by:

The significance level is
and then the critical value can be founded in th chi square table we need a quantile that accumulates 0.05 of the area in the right tail of the distribution and for this case is:

And if the chi square statistic is higher than the critical value we can reject the null hypothesis in favor of the alternative.
Step-by-step explanation:
We have the followign system of hypothesis:
Null hypothesis: 
Alternative hypothesis: 
The degrees of freedom are given by:

The significance level is
and then the critical value can be founded in th chi square table we need a quantile that accumulates 0.05 of the area in the right tail of the distribution and for this case is:

And if the chi square statistic is higher than the critical value we can reject the null hypothesis in favor of the alternative.
It would be 100. Hope it helps!
It would be B (530.7) because if you do 3.14 x 13 x 13 (Or to the second power) Then you get 530.66, the round to the nearest tenths
X intercepts are 2 and -1/2