Which currents have created one of the world's richest fishing grounds?

1. Labrador current and Gulf stream
2. Labrador current and Irminger current
3. Oyashio current and Kuroshio current
4. Both (a) and (c).

Currents influence:

1. temperature
2. rainfall
3. fish population
4. all of the above.

What are tides? Name one factor that causes tides.

What is the time interval between tides? Name the factors responsible for this time interval.