3. The polynomial has 4 terms.
The degree of the polynomial is that of the largest sum of degrees of the variables in any term. That sum is 3+1=4 in the second term. The degree of this polynomial is 4.
4. f(g(x)) = g(x)² +1 = (2x-3)² +1
... f(g(x)) = 4x² -12x +10
Of course, you're familiar with the square: (a+b)² = a² +2ab +b² so you have no problem finding the result when a=2x, b=-3.
hope this !
one that is bigger than 3 1/2