①2个氮原子____.②硫酸根离子____.③2个氧分子____.
(Ⅰ)求数列{an}的通项公式an;
(Ⅱ)设bn= 1log2an+1 ,cn=bn(bn+1﹣bn+2),求数列{cn}的前n项和Tn.
如图是人体部分生理活动示意图,请分析回答:
— ____________ does he do?
— He is a worker. ( )