英文 高中 約1年以前

請問第18題答案為什麼選擇B?

(B) 18. The art gallery is only open on Saturdays and Sundays. (B) In other words (A) For one thing (C) 19. A good chef has to keep sampling all kinds of ingredients (B) in case (A) as if , it is closed on weekdays. (C) Sooner or later (D) To begin with he or she can create new recipes. (D) such that (C) so that

化學 高中 2年以上以前

求題目的過程與解答，問題四延續問題三，謝謝

Problem 3 Creating a 0.1 Normal Solution Suppose you must determine the amount of hydrogen halides (HCI, HBr and HF) in the flue gas leaving a chemical reactor. The emission sampling train for hydrogen halide determination calls for a total of 200 mL of 0.1 N H₂SO4 as an absorbing solution. The absorbing solution will be located on the impingers of the sampling train. How many grams of H₂SO4 should be added to water to create 200 mL of a 0.1 N H₂SO4 solution? > The chemical reaction of H₂O and H₂SO4 is as follows: H₂SO4+H₂O 2H++SO₁²+H₂O 4 > Approximate atomic weights of elements: H=1, S=32, O=16

數學與統計 大學 2年以上以前

有哪位大神可以寫過程給我嗎🙏🙏

Let P(X = x) = 1-3 1-3 , 13₁ x = 74 1 , x = 5 3 x = 8 (1) Obtain μ, o² (**)< (2) Obtain the sampling distribution of X for sample size 34 (3) Obtain E(X), Var (X). Does E(X) = µ? Does Var (X) = ²? Show your n answers.(數字要算出來)

數學與統計 大學 4年以上以前

求救抽樣調查不知道這怎麼寫🙏

The picture is USA map. There are four area, containing N=51 states. The government wants to investigate death rate (death/confirmed) by covid-19 in USA. Asample of n=8 states is selected- How to design and carry outa sample survey for each ofthe following designs. a. Simple random sampling b. Stratified sampling c. Systematicl sampling d. Cluster sampling with stratified sampling In addition, to discuss and comparetheir population mean and bound onthe errorofestimation.