题目内容

One Good Reason to Let Smallpox Live
It's now a fair bet that we will never see the total extinction of the smallpox virus. The idea was to cap the glorious achievement of 1980, when smallpox was eradicated in the wild, by destroying the killer virus in the last two labs that are supposed to have it — one in the US and one in Russia. If smallpox had truly gone from the planet, what point was there in keeping these reserves?
(51)reality, of course, it was naive to(52)that everyone would let(53)of such a potent potential weapon. Undoubtedly several nations still have(54)vials.(55)the last "official" stocks of live virus bred mistrust of the US and Russia,(56)no obvious gain.
Now American researchers have(57)an animal model of the human disease, opening the(58)for tests on new treatments and vaccines. So once again there's a good reason to(59)the virus — just in(60)the disease puts in a reappearance.
How do we(61)with the mistrust of the US and Russia?(62). Keep the virus(63)international auspices in a well-guarded UN laboratory that's open to all countries. The US will object, of course, just as it rejects a multilateral approach to just about everything. But it doesn't(64)the idea is wrong: If the virus(65)useful, then let's make it the servant of all humanity — not just a part of it.

A. In
B. On
C. At
D. For

查看答案
更多问题

入境植物报验时限为15天。()

A. 正确
B. 错误

英译汉:“certificate of damage;certificate of cargo G. A.”,正确的翻译为()。

A. with
B. /
C. in
D. on

检疫发现的我国禁止入境物,来自动植物疫区或来历不明的动植物及其产品,以及动植物性废弃物作返还来源地处理。()

A. 正确
B. 错误

立柱支承着承载的横梁,如图(a)所示。各横梁将其所承受的载荷的一半传递到每一根立柱上,于是立柱受力简图如图(b)所示。已知立柱横截面的尺寸为200mm×200mm,传递到立柱上的载荷FP=100kN。则立柱横截面上的最大正应力为()。

A. -5.0MPa
B. 5MPa
C. -10MPa
D. 10MPa

答案查题题库