Help with Economic Homework?

I was doing my econ homework, and got stuck on these questions. Help would be much appreciated!

1. Niagara Falls is a _____.
a) a private good
b) a common resource
c) a public good
d) a natural monopoly

2. Classify the following as a common resource, a public good, or neither:
i) Logging
ii) A canal through the arctic
iii) mining infrastructure
iv) a mine
v) tourism

3. _____ likely increases climate change.
a) logging
b) shipping through the Arctic Ocean
c) Tourism
d) both A and B

4. Firefighting service is _____ and _____.

a) nonrival; non excludable
b) nonrival; excludable
c) rival; nonexcludable
d) rival; excludable

Help with these questions would be well appreciated!