被称为“第七营养素”的是( )
A:蛋白质
B:维生素
C:膳食纤维
D:无机盐
Who
What's hobby
Where
How
What to do
Bob
reading
Stay at home
/
Read stories
Ann
Doing sports
gym
taxi
Swim and jump
Brandy
…
Shang Hai
train
This is Bob.He is going to①____in Winter Holiday.He likes reading.So he is going to ②____.
This is Ann.She ③____ to the gym.She is going there ④____.She likes ⑤____.She is going to swim and jump.
This is Brandy. ⑥____.She is going there by train.
She ⑦____.
⑧____.
(Ⅰ)若A=B,求a,b的值;
(Ⅱ)若b=3,且(A∩B)⊇B,求a的取值范围.
甲:在鼓面上放一些碎纸屑,敲鼓时可观察到纸屑在不停地跳动
乙:放在真空罩里的手机,当有来电时,只见指示灯闪烁,听不见铃声
丙:吹自制的哨子,上下拉动活塞可使声音变得悦耳或低沉
丁:宇航员在飞船舱外工作时,他们之间的对话必须借助电子通讯设备才能进行.