Someone please help me solve this

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?

How to use order of operation in 20 divide by 4 multiply 5 = 1