What is the domain of f(x) = 3*? A. All nonnegative real numbers
B. All real numbers
C. All real numbers greater than or equal to 3
D. All real numbers greater than 3

The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined. y=−3 is a straight line perpendicular to the y-axis at point (0,−3) , which means that the range is a set of one value {−3}