下列命题中，真命题是

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下列命题中，真命题是（）

A： $\exists x_{0} \in R$ ，使得 $e^{x_{0}} \leq 0$

B： ${sin}^{2} x + \frac{2}{sin x} \geq 3 (x \neq k π, k \in Z)$

C： $\forall x \in R, 2^{x} > x^{2}$

D： $a > 1, b > 1$ 是 $a b > 1$ 的充分不必要条件

上一题下一题 0.0难度选择题更新时间:2012-12-24 01:49:15

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D

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The warm weather outside may look perfect for outdoor exercise. But for those who are not that sporty, ____ could be nicer than having relaxing afternoon tea with a few good friends and taking ____ break?

But are you familiar with the culture of afternoon tea—its origins, what ____ (include), and the proper etiquette (礼仪)? We sum up a few things you need to know about this traditional English custom so that you can enjoy it ____ (much).

While the tradition of ____ (drink) tea dates back to about 3,000 BC in China, it was not until the mid-17th century ____ the concept of “afternoon tea” first appeared in the UK. In 1840, Anna Maria Russell, the seventh Duchess of Bedford, started to ask for a tea tray ____ butter, bread and cakes at 4 pm every day, as she found she was hungry at this time every day and the evening meal in her household was served ____ (fashion) late at 8 pm. She found this new habit difficult ____ (break) and soon invited other ladies in society to join her. This pause for tea quickly became a popular social event. In the 1880s, women of upper class and society would put on gowns, ____ (glove) and hats for their afternoon tea.

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