Question

what mixes mortar ingredients in a powered mixer?
o a vertical agitator
o blades on a rotating horizontal shaft
o paddles on an oscillating shaft
o a rotating drum

Explanation:

A powered mixer for mortar typically uses paddles on an oscillating shaft. This design helps in effectively combining the mortar ingredients. A rotating drum is more common in concrete mixers. Blades on a rotating horizontal shaft might be used in some industrial mixing but not the standard for mortar mixers. A vertical agitator is also not the typical mechanism for mixing mortar in a powered mixer.

Answer:

paddles on an oscillating shaft