写出两个量的比,求出比值,并说说比值的实际意义:
小林做了50道口算题,对了49道.
答对题的数量与做题总数的比是49:50;
49:50=49÷50=98%,表示正确率.
确诊艾迪生病(Addisondisease)最具诊断价值的试验是()
A.螺内酯试验
B.地塞米松抑制试验
C.氢化可的松昼夜节律试验
D.ACTH兴奋试验
E.皮质素水负荷试验
一How do you like our school?
—I think it’s becoming_________. [ ]
A. more and more cleaner
B. more and more beautiful
C. more beautiful and more beautiful
D. clean and clean