76) 2n⁴ × 5n⁴ =
[tex]10 {n}^{8} [/tex]
77) 5v³ × v⁴ × 7v⁴ =
[tex]35 {v}^{11} [/tex]
78) (3n² × 15n³)/5n⁴ = (45n^5)/5n⁴ = 9n
79) (2k⁴)² =
[tex]4{k}^{8} [/tex]
I have used the rules stated above these questions, so when multiplying exponents, a¹ × a² = a^(1 + 2), and 2a¹ × 3a² = (2 × 3)a³.
I hope this helps!