The place value of the 3 in 27.4359 is

Fine the area of the kite. a. 90 sq. units b. 9 sq. units c. 180 sq. units d. 45 sq. units

For a field trip to the zoo, 4 students rode in cars and the rest filled nine busess. how many students were in each bus if 472 students were on the trip

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?