If my experimental hypothesis were 'Eating cheese before bed affects the number of nightmares you have', what would the null hypothesis be?

Question

Poll Results

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Answer 1

Eating cheese before bed gives you fewer nightmares

Answer 2

Eating cheese is linearly related to the number of nightmares you have

Answer 3

The number of nightmares you have is not affected by eating cheese before bed

Answer 4

Eating cheese before bed gives you more nightmares

Discovering Statistics Using SPSS (& sex & dr*gs & rock 'n' roll), 3rd Ed.