 # Aka

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1. Hi, I need help on a project i am doing would anyone know of any other Russian literature that is simmilar, in themes, to Anna Karenina or know where to find any speeches by the Tsar?
2. ## Related rates-blood vessel

Thanks
3. ## Rate of change of Resistors

Hi, can someone help me with this question? Three resistors, R1, R2 and R3, are connected in parallel in an electrical circuit. The total resistance, R, in ohms is given by: 1/R = 1/R1 + 1/R2 + 1/ R3 R, R2, and R3 are increasing at rates of 0.1, 0.5 and 0.7 ohms/s, respectively. Determine the rate at which R1 is changing when R = 50 ohms, R2 = 70 ohms, and R3 = 60 ohms. Find R1 1/50 = 1/R1 + 1/70 + 1/ 60 (1/50)-(1/70)-(1/60)=1/R1 How do you solve something that is in the deominator? the i just Plug eerything in to the equation d/dt 1/R = d/dt 1/R1 + d/dt 1/R2 + d/dt 1/ R3 right?
4. Hi, I am having trouble with this question Assume that a blood vessel, such as a vein or an artery, has the shape of a cylindrical tube with radious R and lenght L. because of the friction at the walls of the tube, the velocity, v, of blood flowing throught the blood vessel is greatest along the central axis of the tube and decreses as the distance r from the axis increses unitl v becomes 0 at the wall. the relationship between v and r is givin by the law of laminar flow, discovered by the French physician Poiseuille in 1840. the law V= p / 4nl (R^2 - r^2) where n is the velosity of the blood and P is the pressure difference between the ends of the tube. If P and L are constant, then V is a function of r. in a typical human artery, the values are n= 0.002 R= 0.008cm, L = 2cm and P= 400 Pa.s. Find the velocity gradiaent ( the rate of change oh v with respect to r) where r= 0.003 cm. can someone tell me the steps to solving thsi problem? Thanks
6. ## replace the functional group of a fat with a phosphate

Thanks
7. ## replace the functional group of a fat with a phosphate

Hi, I have a quick question. When you replace the functional group of a fat with a phosphate what do you get?
8. ## Limits word problems: tow-rope release, helicopter jump

thanks, I'll try that
9. I don't know L'Hospital. We have to solve these quesions using difference of cubes.
10. Hi, I need help with this question is this right? Thanks
11. ## Limits word problems: tow-rope release, helicopter jump

Hi, I need help with this question At a publicity event, Ayida, a stuntperson, will jump out of a helicopter with a jetpack on her back. The jetpack allows her to achieve a net upward acceleration of 4.4m/s^2 for a single interval of maximun lenght 10s. Ayida wants to time the use of the jetpack so that she lands with a zero velocity. a) If the helicpter is 100m hight, when should Ayida turn on her jetpack? When will she land? b) If the helicopter is 200m hight, when should Ayadia turn on her jetpack? when will she land? c) What is the maximum height from wich Ayida can jump to land with zero velocity? I don't know where to start can someone explain this problem thanks.
12. ## How long does a cell live outside a living host?

^ sorry, if they were in air at room temperature, on a surface. Alive as in preforming cell functions, metabolism, reproduction etc.
13. ## How long does a cell live outside a living host?

Squamous cell Gonadotropes Hepatocytes pneumocyte pericyte muscle fiber Red blood cells mast cell Merkel cells Squamous Thanks
14. ## How long does a cell live outside a living host?

Hi, how long does a cell, normal and cancerous, live outside a living host?
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