Question

1. $12mn^{4} cdot 7nm^{4}$

Explanation:

Step1: Multiply the coefficients

$12 \times 7 = 84$

Step2: Combine like variables (m terms)

$m \times m = m^{1+1} = m^2$

Step3: Combine like variables (n terms)

$n^4 \times n^4 = n^{4+4} = n^8$

Step4: Combine all results

$84 \times m^2 \times n^8$

Answer:

$84m^2n^8$