给出下列命题: 命题1:点(1,1)是直线y=x与双曲线y= 1 x 的一个交点; 命题2:点(2,4)是直线y=2x与双曲线y= 8 x 的一个交点; 命题3:点(3,9)是直线y=3x与双曲线y= 27 x 的一个交点; (1)请观察上面命题,猜想出命题n(n是正整数); (2)证明你猜想的命题n是正确.
【单选题】S -Adenosylmethionine is a potent alkylating agent by virtue of its destabilizing sulfonium ion. The methyl group is subject to attack by nucleophiles and is about ______ times more reactive than the ...