Answer:
70. 8x⁴
71. 3n - 10
72. a/5 + 12
Explanation:
70. a number "x" raised to the fourth = x⁴
Product of 8 and x⁴ = 8 × x⁴
= 8x⁴
71. 3 times a number "n" = 3 × n = 3n
3n decreased by 10 = 3n - 10
72. Quotient of a number "a" and 5 = a/5
12 more than a/5 = a/5 + 12