Which statement is true of the function f(x) = Negative RootIndex 3 StartRoot x EndRoot? Select three options.

a
The function is always increasing.
b
The function has a domain of all real numbers.
c
The function passes through the point (3, –27).
d
The function is a reflection of y = .

e
The function has a range of {y|–Infinity < y < Infinity}.

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?