Which are true of the function f(x) = 49()x? Check all that apply.

a-- The domain is the set of all real numbers.
b-- The range is the set of all real numbers.
c--- The domain is x > 0.
d-- The range is y > 0.
e-- As x increases by 1, each y-value is one-seventh of the previous y-value.
f-- The initial value for the function is 7.