问几道英语奥数题1.Where do the marshal(元帅） and the general（将军） have

问几道英语奥数题
1.Where do the marshal(元帅） and the general（将军） have the same rank（地位）?
2.When do 10+10=10,and 10-10=10
3.In the middle of the paper,there is a circle hole with a 5cm diameter on it.you have a coin with 7cm diameter.Now you want pass the coin through the hole.How?write down your method.