鬼——____——____   前——____——____

旁——____——____   更——____——____

如果+3吨表示运入仓库的大米吨数, 那么运出5吨大米表示为(  )

设$\overrightarrow{a}$=(1,1,-2)，$\overrightarrow{b}$=(x,y,z)若x²+y²+z²=16，则$\overrightarrow{a}$$·$$\overrightarrow{b}$的最大值为____ 

    There's an 1 tree behind the Crisps' house. Jack Crisp is standing near the tree. There are some apples on the tree. Jack is looking 2 the apples. They are big and red

    Jack is 3. He wants to eat an apple. Jack isn't tall. He can't reach the apples. He is putting a box under the tree. Can he reach the apples now? No, he can't. He is too short.

    Here comes Paul Crisp. He is Jack's 4, "Hey, Jack! What are you doing?"

"Please help me? I can't reach the apples."

    Paul picks up 5 apples and says, "Here you are, Jack. One for you, and one for me!"

    "Thank you, brother."