Division of a polynomial by a polynomial

Q. Factorize the following algebraic expression:

$25-p^2-q^2-2pq$

Q. Simplify the given expression:
$(3y+12b)(5a-b)÷(y+4b)(25a^2-b^2)$

1. $\frac{3}{5a+b}$
2. $\frac{5}{3a+b}$
3. $\frac{3}{5a-b}$
4. $\frac{3}{a+5b}$

Q.

Dividing $x(3x^2-27)$ by $3(x-3)$ gives $x^2+3x$.

1. False

2. True

Q.

Express the following difference in the simplest form $?$

$\frac{5}{\mathrm{x}+5}-\frac{2\mathrm{x}+5}{{\mathrm{x}}^2+9\mathrm{x}+20}$