1

Arrange the first school first: C3 1 times C62.

Arrange the second one: C2 1 (doctors choose 2 1) times C42 (nurses choose 2 from 4).

So C3 1 times C62*C2 1 times C42=540.

2

Arrange 3 doctors to go to 3 schools A33

Arrange two nurses to the first school C62,

Arrange two nurses to go to C42, No.2 school.

So A33*C62*C42=540.