— The cars made in Germany are more expensive than ________ made in Japan.
— Yes, I can't agree more. But they're much better.
A:it
B:that
C:those
D:ones
已知:RCOO →SOCl2 RCOCl(酰氯,化学性质十分活泼);
RCOCl+NH3→RCONH2+HCl
根据以上信息回答下列问题:
设等比数列 {an} 的前 n 项和为 sn ,已知 an+1=2sn+2(n∈N*) .
(Ⅰ)求数列 {an} 的通项公式;
(Ⅱ)在 an 与 an+1 之间插入 n 个数,使这 n+2 个数组成公差为 dn 的等差数列,设数列 {1dn} 的前 n 项和 T ,证明: Tn<1516 .
可导致环境人口容量降低的因素有()