小官极速搜题练习工具
一个近视眼的远点在眼前40cm处,他应佩戴焦距多大的眼镜? A.40cmB.-40cmC.20cmD.-20cm正确答案:-40cm
Copyright © 2026 极搜搜 | Powered by Specia WordPress Theme 沪ICP备2021005711号-2