下列哪个指标越小，表示用该样本均数估计总体均数的可靠性越大（）
A.CV
B.S
C.S
D.R
E.S2
参考答案：C
Part A You will hear a lecture about shingles, an infectious disease. As you listen, answer Questions 1 to 10 by circling TRUE or FALSE. You will hear the talk ONLY ONCE. You now have 1 minute to read Question 1 to 10.Questions 1 to 10:
After recovering from the blisters, you may have some scars remained on your body.
采用于胶法制备乳剂时，在初乳中植物油、水、胶的比例通常为（）
A.1：1：1
B.2：2：1
C.3：2：1
D.4：2：1
E.5：2：1
