Town officials want to estimate the number of households that own a dog. Answer the following.

(a)	Which of the following surveys probably would best represent the entire population of households?
	20 households with a front yard are randomly selected; 9 own a dog.
	20 households within a mile of a park are randomly selected; 10 own a dog.
	20 households are randomly selected from the town; 7 own a dog.
(b)	There are 1000 households in the town. Using your answer from part (a), estimate the number of households that own a dog.
	households