What was the mit'a and how was it paid?

The mit'a was a public duty taxes, paid in labor by men of the ayllu. To pay tax, men might repair roads, build storehouses, or work in mines. Hope it help!

A mit'a is a obligatory or necessary public service in the society of the Inca Empire. " It was effectively a form of tribute to the Inca government", from the forming of labor . Inside the Inca Empire, many public services were needed and required in the community-driven projects. Some examples of buildings of road network;  military service that were also mandatory and others. To end this, Incas were so lazy and if they were lazy, he or she would have to jump off the cliff and do other dangerous requirements.

The answer is professionals such as attorneys.