Find limit for the following functions:

a$)\underset{x-2}{lim}\frac{x^2+5x+5^2}{x^2-5}$

b$),\underset{x6}{lim}\frac{x^3-4x^2}{x-4}$

c$),\underset{x}{lim}(3x^3-x^2+9)$

d$),\underset{x5}{lim}\frac{6\sqrt[\phantom{2}]{x-4}}{8x+10}$

e$),\underset{x0}{lim}\frac{2x^2}{3x^2+7}$