The particle rotates around a fixed circular orbit. It just returns to the starting point after rotating for 300 miles(one circle). What is the radius of the orbit?
-
A$$\frac{150}{π}$$
-
B$$\frac{90}{π}$$
-
C$$\frac{60}{π}$$
-
D$$\frac{30}{π}$$
-
E$$\frac{15}{π}$$
显示答案
正确答案: A