The range of sin(x) is [-1,1].
No matter what the value of x,pi,pi/2,pi/4,pi/6,-pi/2,etc the value of sinx will always be between -1 and 1(both included)
It would be B, the second triangle.
Hope this helps.
Answer:
The probability that between 79% and 81%of the 500 sampled wildlife watchers actively observed mammals in 2011 is P=0.412.
Step-by-step explanation:
We know the population proportion π=0.8, according to the 2011 National Survey of Fishing, Hunting, and Wildlife-Associated Recreation.
If we take a sample from this population, and assuming the proportion is correct, it is expected that the sample's proportion to be equal to the population's proportion.
The standard deviation of the sample is equal to:

With the mean and the standard deviaion of the sample, we can calculate the z-value for 0.79 and 0.81:

Then, the probability that between 79% and 81%of the 500 sampled wildlife watchers actively observed mammals in 2011 is:

Check the picture below.
make sure your calculator is in Degree mode.