1) $$12pk^3 \cdot (-3p^4k^2) = 12 \cdot (-3) \cdot p \cdot p^4 \cdot k^3 \cdot k^2 = -36p^{1+4}k^{3+2} = -36p^5k^5$$.
Ответ: $$-36p^5k^5$$