Tony's father, Mr. Baker, lost his job last year. But now, he has his own fast food shop. It's not very big, but it sells a lot of food, drinks, desserts and soup. Many people like the hamburgers there. Today is Sunday. Tony got up very early. After breakfast, he went to his father's shop and made a line graph（线状图表） for him to show the number of hamburgers he sold. Now please look at the graph and today's menu to choose the best answer.

—I agree.

已知|a|=3，b²=16，且|a+b|≠a+b，则代数式a﹣b的值为（    ）

Our parents ____ ____ ____ ____ us every time we leave home.