determine whether the function is continuous at the given x-value. If discontinuous ,state the type of discontinuity (jump, infinite, or point)

2.f(x)= {x^2+1 if x<0,x if x _>0} x =0.

3.describe the end behavior of y = x^4 -3x +1.

4. locate and classify the extrema for the graph of y=2x^3 - 6x.

5. The function f(X)=x^5/5 - 4/3 x^3

plz i need help, i need them before two days. Thx very much.(Crying)