Help my friend out I cant help him in too busy with my work smh

What is the 12th term of b(n)=-4-2(n-1)

This is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 4 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 3 terms. this is a rational expression because the denominator contains a variable. this is a polynomial with 5 terms.

What is the effect on the graph of the function f(x) = x2 when f(x) is changed to f(x) − 4?