I have this really hard puzzle that i need to solve for my class but I'm having a hard time. Can someone please help me?

Question

I've been given a list of places and a list of hints and I have to find out which place fits the hints that are given. The places are:

Tokyo, Japan
Singapore City, Singapore
Melbourne, Australia
La Paz, Bolivia
Montreal, Canada
Sao Paulo, Brazil
Rio de Janeiro, Brazil
Mexico City, Mexico
Buenos Aires, Argentina
Cairo, Egypt

The hints are:
1. The city is on the mainland of a continent
2. The city is located on the Western Hemishphere
3. The city is located entirely north of the Tropic of Capricorn
4. The city is located entirely south of the Tropic of Cancer
5. The city is located on a coast

After narrowing my choices I only have La Paz, Bolivia
Rio de Janeiro, Brazil
Mexico City, Mexico
and Buenos Aires, Argentina left.

Please help!! Thanks
-MC

Answer 1

---And take Bolivia out of that because it's not located on a coast.
-MC

Answer 2

Rio is located on a coast.

Do you know where the Tropics of Cancer and Capricorn are? Check a map to see if any of those places would fit.

Answer 3

Is it Rio de Janeiro, Brazil?
-MC

Answer 4

yup

Answer 5

Thanks!!
-MC