You draw perpendicular bisectors to find the center of a circle circumscribed about a triangle. Hook me up with 5 stars :)
You could rewrite

as

and be tempted to cancel out the factors of

. But this cancellation is only valid when

.
When

, you end up with the indeterminate form

, which is why

is not a zero.
Answer:
Step-by-step explanation:
Males proportion 
Females proportion 

(one tailed test for comparison of proportions)
Test statistic = 
=-1.3641
Here p= combined proportion = 
p value = 0.0869
Since p >0.05, accept null hypothesis.
The evidence does not suggest a higher proportion of females are annoyed by this behavior
Answer: C
The graph is continuous because there can be fractional values for time