将下列句子重新排序，使其成为一段通顺的对话

a. At half past seven.

b. Good morning, Bob. What time did you have breakfast today?

c. I had a hamburger and some cola. I often have these for breakfast.

d. What did you have for breakfast?

e. Good morning, Joe.

f. That's not healthy. You should eat vegetables and drink some milk.