设随机变量X~B(2,P),随机变量Y~B(3,P),若P(X≥1)=59,则D(3Y+1)=( )
学完生殖、发育、和遗传等知识后,张明同学构思了一部科普动画片,部分画面及解说词如下:我是一只快乐的家鸽,从一枚受精卵开始,我踏上了奇妙的生命旅程.
巴西是南美洲经济实力最强的国家,2016年巴西里约热内卢奥运会即第31届夏季奥林匹克运动会,于2016年8月5日至8月21日在巴西里约热内卢举行。读图回答下列问题。
Learning English online
Ways to learn English
English magazines, newspapers and radio
Various kinds of English learning1.
Benefits of online learning
People around the world can visit them 2.
People can get answers instantly on the Internet.
People can learn what they need anytime and search for useful3 without leaving home.