New strains of viruses are transmitted to man by______.

A． a type of pig

B． diseased lower animals

C． a group of migrating birds

D． a variety of means

[名词解释] 品系（strains）

[单选题]When transmitted by a reduction gear, diesel engine speed is reduced and the torque available for workA．remains the sameB．is reducedC．is increasedD．is eliminated

[单选题]The new traffic law is mainly intended to .A． limit the number of foreign vehicles entering BritainB． increase the British movement’s additional incomeC． lower the rate of traffic accidents and injuriesD． get foreign drives to appear in count

[单选题]E．New archaeological discovers suggest that trade between Europe and Asia along the Silk Road probably began in some form. many countries earlier than once thought. The findings, coupled with a widening range of scientific and historical research cou

[名词解释] 条件缺损病毒（coditionally defective viruses）

[单选题]（ 29 ）当使用 SomeThread t=new SomeThread() 创建一个线程时，下列叙述中正确的是A． ） SomeThread 类是包含 run() 方法的任意 java 类B． ） SomeThread 类一定要实现 Runnable 接口C． ） SomeThread 类是 Thread 类的子类D． ） SomeThread 类是 Thread 类的子类并且要实现 Runnable 接口

[试题]New and more up-to-date methods have to______(find)for collecting earthquake data and analyzing it.

[判断题]In most supply chains， customer requirements are transmitted in the form of

[单选题]John: Mary isn't going to New York next week.Rose: ______

[单选题]What can we know about viruses and bacteria from the fourth paragraph?A.Vir