Answer: See explanation
Step-by-step explanation:
The null hypotheses for the above scenario will be the statement of no effect and it'll be the mean weight of the bag that filled will be 420 grams.
H0: μ = 420
The alternative hypotheses for the above scenario will be that the bag isn't filled with 420 grams. They are either underfilled below 420 grams or overfilled above 420 grams.
Ha: μ ≠ 420