Multiplication of polynomials questions

1. x(5x² - 2x + 3)
2. (8x⁵)(3x²)
3. 7x(4x² + 3x + 12)
4. 12x⁴ * 10x²
5. 10x(5x² - 9x + 22)
6. (21x⁹)(8x³)
7. 3x(17x⁴ + 5x² + 13)
8. 15x² ● 5x⁸
9. ^{x(20x2 + 10x + 100)} 
10.   multiply the polynomial(3x⁶+2x⁵+5) by the polynomial (4x² + x + 5)
11. Multiply the polynomial(3x+4) by the polynomial(5x⁴ +7x³ + 5x)
12. Multiply (2x⁷ +4x² +3x)(3x⁸+ 2x³ + 15x)