Answer: a. Each term in Bill's pattern is twice the value of the corresponding item in Jan's pattern.
Explanation:
Jan created a pattern by adding 3 and Bill created a pattern by adding 6.
6 is twice the value of 3 so Bill's terms will be twice the value of Jan's corresponding terms as well.
To prove it:
12 is twice the value of 6
18 is twice the value of 9
24 is twice the value of 12