Answer:
Birds

Gerbils

Fish

Hamsters

Explanation:
From the question we are told that:
Sales
Number of birds

Number of gerbils

Number of fish

Number of hamsters
Generally the frequency for birds
is mathematically given b



Generally the frequency for Gerbils
is mathematically given b



Generally the frequency for fish
is mathematically given b



Generally the frequency for fish
is mathematically given b


