计算题.
1.At 12 noon my watch was correct. However, it then started to lose 18 minutes per hour.
Four hours ago it stopped completely and is now showing the time as 15:30.
What is the correct time now?
Answer: _____________________________________________________________
2.![](https://img.ixiawen.com/uploadfile/2017/0727/20170727023427774.png)
What value of weight should be placed on the scales to balance?
Answer: _____________________________________________________________