Is square root 1 minus cosine squared theta = −sin θ true? if so, in which quadrants does angle θ terminate?

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

Ineeeeed this is due tomorrow and i dont know the answer can you find all the exponents

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.