下列说法正确的个数为①对于不重合的两条直线，“两条直线的斜率相等”是“两条直线平行”的必要不充分条件；②命题“∀x∈R，sinx≤1”的否定是“∃x0∈R，sinx0＞1”；③“p且q为真”是“p或q

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下列说法正确的个数为（）

①对于不重合的两条直线，“两条直线的斜率相等”是“两条直线平行”的必要不充分条件；

②命题“∀x∈R，sinx≤1”的否定是“∃x₀∈R，sinx₀＞1”；

③“p且q为真”是“p或q为真”的充分不必要条件；

④已知直线a，b和平面α，若a⊥α，b∥α，则a⊥b．

A：1

B：2

C：3

D：4

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C

Picture	Description(描述)
____.	A. They're very smart. People kill them for their ivory.
____	B. Do you often watch him play basketball? If you do so, what do you think of him?
____	C. —I can't find my keys. —Let me help you.
____	D. It's good exercise and also it's good for our environment (环境).
____	E. I always get up at 6 o'clock in the morning.
	F．It means that you can't take photos.