Someone help me fr :'-( Determine whether each sample may be biased. Explain.
5. Rickie surveys people at an amusement park to find out the average size of people's immediate family

6. Theo surveys every fourth person entering a grocery store to find out the average number of pets in people's homes.

7. A biologist estimates that there are 1,800 fish in a quarry. To test this estimate, a student caught 150 fish from the quarry, tagged them, and released them. A few days later, the student caught 50 fish and noted that 4 were tagged. Determine whether the biologist's estimate is likely to be accurate.

NO FILES OR I REPORT grr >:-(