According to a genetics model, plants of a particular species occur in the categories A, B, C, and D, in the ratio 9:3:3:1. The categories of different plants are mutually independent. At a lab that grows these plants, 218 are in Category A, 69 in Category B, 84 in Category C, and 29 in Category D.
1. The null hypothesis is:
a)The model is good.
b)The model isn't good.
c)Too many of the plants are in Category C.
d)The proportion of plants in Category A is expected to be 9/16; the difference in the sample is due to chance.
2.The alternative hypothesis is:
a)The model is good.
b)The model isn't good.
c)Too many of the plants are in Category C.
d)The proportion of plants in Category A is expected to be 9/16; the difference in the sample is due to chance.
3. Under the null, the expected number of plants in Category D is ______.
4. Degrees of freedom = _______.