-12s^2 + 11st - 2t^2.
Step-by-step explanation:
(-3s + 2t)(4s - t)
= -3s(4s - t) + 2t(4s - t)
= -12s^2 + 3st + 8st - 2t^2
= -12s^2 + 11st - 2t^2.
d and e