( Monitoring heart patients' exercise as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. ) A. Monitoring heart patients' exercise as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. B. Monitoring the exercise of heart patients, as well as athletes excersing, is now done by small transmitters broadcasting physiological measurements to nearby recording machines. C. Small transmitters broadcasting physiological measurement to nearby recording machines are now used to monitor the exercise of both heart patients and athletes. D. Broadcasting physiological measurements to nearby recording machines, small transmitters are now used to monitor heart patients' exercise, as well as athletes exercising. E. Both athletes exercising and heart patients' exercise are now monitored by small transmitters broadcasting physiological measurements to nearby recording machines. 答案是C，错选了E。排除C的原因是感觉主语很长，头重脚轻。第一遍看原文的时候感觉exercise和exercising不平行，但是每个选项读下来发现都是这个形式，（当时没有注意到C的形式）于是就认为这个可能不是考点。E的错误是exercise和exercising吗？麻烦老师讲解。

请问这一题的解题思路

求问解题思路

求问解题思路

条件一：（30+⏹）（20+🔼）=864化简为20🔼-🔼^2=64 然后从2开始带入，得出当🔼=4时成立。条件二：⏹✖️🔼=24得出3、8和4、6两组可能解，分别带入，只有36和24成立，所以条件二充分。请问以上这个解题思路对吗，或者说有更简便的？

第14题 请徐老师解答 谢谢！

请问这道题的解题思路

第13题: 听老师jj课里讲的说选C，我不太明白条件2的分析，老师上课说条件2，若st同号，上式取等号，若st一正一负时，上式是小于号。那不就可以通过条件2直接判断上式大于号不成立吗，也就是答案是No。请老师更正下我的思路。

请徐老师讲下这两道题：这两个都做对了 但是感觉做的时候不太自信，想了一会，想听下老师的思路。谢谢老师！

麻烦徐老师讲一下Q9，选了E。我的思路是分析rounding后estimate的最大和最小的差值。

请徐老师讲一下Q7思路。读题是不是很明白题意说的到head的概率不是1/2。