大一公衛系微積分，求第二題解

公衛系 微積分期末考 (28/12/2018) 1. Use the Laplace transform to solve the differential equations. (1) j(t)+2y(t) = x(t), y(0)=1, x(t)=10, t20 (20) (2) Intravenous glucose is a treatment. Disposed at a fixed rate k grams per minute inputs into the blood, while blood glucose will be converted to other substances or moved to another place, at a rate proportional to the amount of glucose in the blood, the proportionality constant is a (a> 0), the initial amount of glucose in the blood is M. A. Find the variation in the amount of glucose in the blood (15) B. Determining the equilibrium, the amount of glucose in the blood. (5) = 2. SI Epidemic Model : The size of the population, n+1, remains fixed. Let i(t) be the number of infectives at time t, and let s(t) be the number of individuals who are susceptible. Given an initial number of infectives iO), we would like to know what will happen to i(t). SI Epidemic Model is described by the differential equation. di(t) = k·i(t).s(t) ......(5.1) dt i(t)+s(t)=n+1 i(0)=i, (1) Solve this differential equation of the SI Epidemic Model (5.1). (10 h) (2) What is the peak times t of the epidemic spread? (10) 3. Consider the Two-compartment physiological models and is shown in figure 1. C1 (t) represent the drug concentration in the first compartment and C2 (t) represents the drug concentration in the second compartment. Vi and V2 represent the compartment volume. Use the first order linear differential equation general solution to solve the C1 (t) (20 ) and use the Laplace transform to solve C2 (t). 【20 分). | 世」!()

請問這題⋯

3. If f(x) = et – 2,0 < x < 2, find the Riemann sum with n = 4 correct to six decimal places, taking the sample points to be midpoints. What does the Riemann sum represent? Illustrate with a diagram.

求解答案是否正確

Multiple-choice questions: (70 points) write the letter of statement that is not true: 1. A.B.U The Drude Model: (a) It is a classical approach using concepts from the kinetic theory of gases. (b) A relaxation-time approximation is used where the probability of collision is l/t. (c) No forces act on the electrons in between collisions. (d) It predicts accurately the electronic heat capacity of metals. 2. The Sommerfeld Model: (a) The crystal potential is replaced by an average Coulomb potential. (b) The separation of states is so close that a continuum model can be applied. (c) The electrons are highly localized due to a strong crystal potential. (Q) The energy of the highest occupied state at 0 K is the Fermi energy. 3. Density of states in k-space, N(k): (a) N(k) is determined by the boundary value conditions. (b) For lattices in any dimensions, N(k) is constant in k-space. (C) N(k) depends on the direction and magnitude of k. (d) It is directly proportional to the volume of the crystal. E影響, c 4. The Fermi surface of a metal: (a) is responsible for many of the transport properties of the metal, (b) depends on the nature of the chemical bonds, (c) is always a sphere, (d) can involve mixing of electron orbitals. ✓ 5. The conductivity of a material () increases with the mobility of its carriers, (b) increases with the density of carriers, (C) it is inversely proportional to the energy gap. cogu changes with temperature. 6. BID Plasmons: (a) They are an important characteristic of the Sommerfeld electron gas model. (b) Plasmons occur spontaneously in metals. (c) They are related to charge density oscillations. (d) The Plasmon energy is typically of the order of 10 eV. The Fermi energy Ef in intrinsic semiconductors 8) is usually close to y E, at OK (b) it ACiD. can increase or decrease with temperature depending on the ratio of hole and electron effective masses, (c) it represents the point at which the probability of occupation is 12, even though there may not been any states with that energy, (d) its value relative to the electronic bands must remain unaffected in the presence of defects or interfaces.

2-14的C謝謝！

b. 78 d. 214 P2-12. Change the following decimal numbers into binary using the alternative method discussed in Example 2.18, showing your work: a. 358 c. 4 1364 = O b. 12 3/32 d. 12 57128 P2-13. In a positional number system with base b, the largest integer number that can be represented using k digits is ble – 1. Find the largest number in each of the following systems with six digits. a. Binary c. Hexadecimal b. Decimal d. Octal P2-14. Without converting, find the minimum number of digits needed in the destination alodine system for each of the following cases: a. Five-digit decimal number converted to binary. 19 din b. Four-digit decimal converted to octal. c. Seven-digit decimal converted to hexadecimal.

求高手幫忙

1(35%) Determine the Fourier series representation of the periodic signal x(t) shown in Fig. 1. Plot its frequency spectrum Ck/ versus frequency 0, 020, where Ck is the Fourier series coefficient. xt (0) 20 -6 -4 -2 0 2 士 4 16 10 十-20 Fig. 1

請幫助我這一題cash flow的問題，拜託大家，謝謝

Qun: Chl3 part 3 Powell Corporation's comparative statements of financial position are presented below. POWELL CORPORATION Comparative Statement of Financial Position December 31 2020 Land € €18,000 Buildings 70,000 Accumulated depreciation-buildings ( (15,000) Accounts receivable 18,200 Cash 21,570 Total €112,770 2019 €26,000 70,000 ( (10,000) 23,400 10,700 €120,100 Common Stock Retained eamings Accounts payable Total € €75,000 25,400 12.370 €112,770 € €69,000 20,000 31,100 € €120,100 Additional information: 1. Ignore income tax. Netincome was €27,900. Dividends declared and paid were €22,500. 2. All other changes in non-current account balances had a direct effect on cash flows, except the change in accumulated depreciation. The land was sold for €5,900. Instruction Prepare a statement of cash flows for 2020 using the indirect method.

求解第四第五題!!!電機的 謝謝😭🥺🥺🥺 拜託看到盡快><

2. The circuit in Fig. 2 represents an energy storage bank with vi(0)=-3 V, v2(0) = 5 V, v3(0)=-5 V. (a) If the switch Si is closed at tı > 0, find the values of vi, v2, and v3 after ti. (b) Following (a), if the switch S2 is closed at 12 >ti. Find the final values of vi, vz, and va after 12. 3. Let iz(0) = 0. Find the current il(t) of the circuit shown in Fig. 3 for t> 0. 22 w 22 32 1 ] 322 + 8t u(t) A 22 2H 1:6 8u(1) V 台Fv() 3i Fig. 3 Fig. 4 4. Let vo(0-) = 0. Find the voltage ve() and current i(1) denoted in Fig. 4 for t> 0. 5. The switch shown in Fig. 5 is closed for a long time before t = 0. When the switch is open at t = 0, find i(t) for t < 0 and > 0. i=0 =0 212 622 W + 392 8 V 0.510) 2=vd) - Fig. 5 FE final Sophie de EES-B22.pdf 20210611_115335.jpg 20210611_115320.jpg 18.pdf

求解，可以教我怎麼算嗎😭

2 Two individuals, 4.455Cc2D2D5e and qqgppccddee, are mated (配對) to produce anFl that is self-fertilized io Produce F2. Ifthe capitalletters (大寫) represent dominant, and all five loci are independently assorting alleles: 人 1) How many different genotypes will oceur in the F2? 2) What proportion (比例) ofthe F2 genotypes will be recessive for all five loei (基因座)? 語玉2

財管題目，求解😭😭😭

@ 今天,小陳正在慶祝她的 40 歲生日。她的願望是希望在 65 歲退休時,退休後 的 20 年間,每年生日時都能從儲著帳戶中提出$240,000。第一次提款時間是她 的 66 歲生日。小陳打算參加兆豐銀行零存整付專案 (年利率 2%) ,每年生日 時都存入一筆等額現金到此專案帳戶 ,做為退休基金之用。 (1) 如果小陳從 40 歲開始存款,一直到 65 歲 (最後一筆存款是 65 歲生日) ,請問 她每年要存入多少錢才能支應她的退休需求 ? (可先找出以下條件:預計幾年後 退休 ? 退休後每年可領金額 ? 退休儲蓄金可使用年限? ) (2) 假設小陳剛剛很幸運地中了大樂透,所以她決定要改變計畫,不要每年存入等 額的現金,而是在40歲生日時直接存入一大筆可以滿足她退休計畫的錢。請問 大樂透獎金至少要多少錢才夠呢 ? 如果大樂透獎金為$1,500,000 , 請問足以支 應退休計畫嗎?若是可以,請問小陳退休後每年可提領的金額增加多少? 若是不 足以支應,請問小陳每年要再存入多少錢才能支應她的退休需求? ( 假設不考慮 稅賦等影響因素 ) (3) 假設小陳的公司提出員工分紅計畫 ,每年會有$12,500 元分紅直接存在她的儲蔡 帳戶。此外,小陳預期在她 55 歲生日時,可從一筆家族信託基金領到$120,000, 到時她也會把這筆基金直接存到她的退休金帳戶。請問,若有分紅計畫和家族 信託基金的幫助,小陳每年應該還要存入多少錢,來支應她的退休計畫呢?

有人可以麻煩幫我看有沒有寫錯嗎🙏🙏

Busines5s comrmunmlecat or fora supermarket 選避1 is abuyer IT Rick Parry 15 凡 記全8 et tative ofakey supplier. fion with words from feeg7fF9#-f7#4e9 fojdf do ol do 7eye和77 ee-fojueef 1/olt 7 泌 ggz5 777CC 之 gg7zf 1 0 【///234 One of W2 1 CK Marcel, 」 4 2上全 our guest5. MarceL 3 Patti Kline. 5he works with Longridge,one ot our 宙他9 biggest suppliers. ry \ Ma cel ? 還 VGy le to imeet youu 1 iceto ice _、M9人一 , too. So Marcel, Wo _ GoMoxk_GS exactly? 2 反- 守eel WellL Tm in charge of all our stores in the south of England. 關代二?Thatmustbevery 毗戰din8. You know, alot of responsibility. dto talk to someone over there. seeing you, Pattt. Keep card