Answer:
a)
b) 
c) Since the p value is higher than the significance level provided we have enogh evidence to FAIL to reject the null hypothesis and we can't conclude that the true means are different at 5% of significance
Step-by-step explanation:
Information given
represent the mean for 1
represent the mean for 2
represent the population standard deviation for 1
represent the population standard deviation for 2
sample size for the group 1
sample size for the group 2
z would represent the statistic
Hypothesis to test
We want to check if the two means for this case are equal or not, the system of hypothesis would be:
H0:
H1:
The statistic would be given by:
(1)
Part a
Replacing we got:

Part b
The p value would be given by this probability:

Part c
Since the p value is higher than the significance level provided we have enogh evidence to FAIL to reject the null hypothesis and we can't conclude that the true means are different at 5% of significance
Answer:
ngee hirap Naman niyan sayang

It is true only whenever x tends to 0(zero)
it is not importent that x be in radian or in degree.
So the problem ask to simplify the trigonometric function in your problem and base on the expression and using the theory in simplifying trigonometric function, the answer would be letter B. 2 sec^2 theta. I hope you are satisfied with my answer and feel free to ask for more