升压过程中汽包热应力是由（）和内外壁温差引起的。
参考答案：上下壁温差
---Mum, I’m really ________ about the result of the exam.
---Cheer up. I believe you can be successful.
A．patient
B．satisfied
C．unhappy
D．pleased
与36 ÷3+6的结果相等的算式是[ ]
A．6+36÷3
B．36÷(3+6)
C．36÷6+3
