2. A lake contains 3 species of fish. There are estimated to be 1400 trout, 600 bass and 450 pike in the lake. A survey of the health of the fish in the lake is carried out and a sample of 30 fish is chosen.
- Give a reason why stratified random sampling cannot be used.
- State an appropriate sampling method for the survey.
- Give one advantage and one disadvantage of this sampling method.
- Explain how this sampling method could be used to select the sample of 30 fish. You must show your working.