问题 选择题

直角三角形中斜边上的中线长为2.5cm,周长为12cm,则三角形的面积为(  )

A.3cm2

B.6cm2

C.12cm2

D.24cm2

答案

设直角三角形的两条直角边是a,b

根据直角三角形斜边上的中线等于斜边的一半得斜边是5

根据勾股定理得:a2+b2=25①

再根据周长得a+b=7②

∴ab=[(a+b)2-(a2+b2)]÷2=(49-25)÷2=12

∴S=

1
2
ab=6

则面积是6.

故选B.

判断题
单项选择题

For any export-oriented American business, an invitation to join the U. S. Commerce Secretary on one of his trade missions abroad is like a World Series ticket—the hottest seat in town, and something you might pay top dollar to get. In 1992, Bill Clinton promised that his Administration would fight hard to help American companies win foreign business. That’s a worthy goal of trade missions, which provide selected chief executives with priceless connections to the corporate heads and government officials of other nations.

But under the late Commerce Secretary Ron Brown were the Democrats "selling" seats, using those missions to reward party donors And did the trips serve the dual purpose of drumming up (招徕) more donations abroad Those are the questions at the heart of the lawsuit filed by the non-profit conservative group Judicial Watch Inc. Last week, thousands of pages of Commerce Department documents have been turned over to the group.

The Commerce Department papers clearly indicate many corporate contributors expected their money to earn them special consideration when seats were being handed out on the secretary’s plane. In a letter addressed to Deputy Assistant Commerce Secretary Jude Kearney, C. Payne Lucas, a development-organization executive suggests he should be added to a mission headed for South Africa president Nelson Mandela. In another, Philip Verveer, a Washington attorney, recommends a place on 1994 mission to India for William Ginsberg, chief executive of Cellular Communications International. "Oinsberg was an early financial supporter of Clinton/ Gore campaign," Verveer writes.

These missives occasionally show federal officials urging their superiors to favor donor executives. In one letter, Reta Lewis, a political affair official at the White House, urges that a spot be found for Gerald McGowan, a partner in a Washington law firm, on a trade mission to Indonesia or India. For one thing, Lewis points out, McGowan qualifies as D. N. C. "managing trustee (托管人, 理事)," someone who gives $100,000 a year to the Democratic National Committee.

But did the White House always give its funders the heavy preference they expected That is another story.

Which of the following is implied in the passage().

A. The White House disappoints its funders by refusing to give them heavy preference they expected.

B. Financial supporters in presidential election can always be rewarded by an important position in the government.

C. Participation in the Commerce Secretary’s trade missions abroad might bring donors abundant rewards.

D. Financial contributors in presidential election are inevitably clearly recorded in Commerce Department documents.