Choose the sentence that has no misplaced or dangling modifiers

What are the constants in this expression? -10.6+9/10+2/5m-2.4n+3m

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

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