【演示实验】将一定量的稀H2SO4加入到盛有NaOH溶液的小烧杯中．
A: Hey, John's birthday dinner is next week. Let's ____ about the food.
B: Sure. How ____burger, vegetable salad, and some fruit?
C:____ good. John likes hamburgers.
A: Oh, I ____ like salad.
C: But John likes salad, and it's his birthday.
A: Yes, you're right. What about the fruit?
B: I think John likes strawberries and apples.
C: OK. Let's have ____ and apples then.
如图，已知经过原点的抛物线y=ax2+bx+c（a≠0）的对称轴是直线x=﹣1，下列结论中：
①ab＞0，②a+b+c＞0，③当﹣2＜x＜0时，y＜0．
正确的个数是（ ）
为了人类世世代代都有可利用的各种资源和美好的生活环境，人类必须（ ）
