单选题If the ratio of the area of a sector to the area of the circle is 2：3. what is the ratio of the length of the arc in the sector to the circumference of the circle?A3/2B2/3C4/9D1/4E9/4
单选题
If the ratio of the area of a sector to the area of the circle is 2：3. what is the ratio of the length of the arc in the sector to the circumference of the circle?
A
3/2
B
2/3
C
4/9
D
1/4
E
9/4
参考解析
解析：
The ratio of sector area to circle area is proportional to the ratio of sector arc length to circumference.
The ratio of sector area to circle area is proportional to the ratio of sector arc length to circumference.
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