Homework Help

I have this question for school but I have no Idea how to answer it...Please Help.... Draw Curves showing how the relative amounts of a radioactive parent and a stable daughter can yeild an absolute date for a rock sample.

Hi. I have to write a proposal for an experiment I will be doing. I need to prepare some tissue samples to run a SDS-PAGE. I would like to know how do I know what pH to make my extraction buffer for tissues like beef, turkey, soybeans....etc.

Hi , Nice to meet you all. I have a few questions on Chemistry. 1. What are transition elements? Are they metals or non-metals? 2. Can elements be ion and molecule? Are there any difference? 3. What 'element' can form an ionic bond and covalent bond? 4. What are the differences between conductor and electrolyte, insulate and non-electrolyte? 5.What is the difference between mass(i.e. a.m.u) and weight(kg)? Thanks in advance. I really want to know the answers

Anyone here be able to link me to some tuts on balancing chemical equations? i googled for about 5 minutes and came up with nothing.

Yo, I am a 16-year-old student who struggles with probability. Pardon my grammar. A bag contains 8 green and 4 red balls. 6 balls are drawn at random in succession from the bag without replacement. What is the probability that the colours appear alternately? Does this question require a probability tree? Do tell me if it does, because we have to choose 6 balls and I think it is too complicated for one. So on seeing that it is "without replacement", I just did this. G R G R G R => 8/12 x 4/11 x 7/10 x 3/9 x 6/8 x 2/7 = 2/165 R G R G R G => 4/12 x 8/11 x 3/10 x 7/9 x 2/8 x 6/7 =2/165 And then I add them up because they are mutually exclusive events. …

I hate my health class.. These questions are NOT found in my book. Argh. 1. The first stage of alcoholism is characterized by a) malnutrition b) defensive behavior c) rationalization of drinking behavior d) reverse alcohol tolerance 2. A major factor in traffic accidents, homicides, and suicides for 16 to 24-year-olds is a) alcohol use b) smoking cigarettes c) affiliation with gangs d) psychological disorders My guess: C and D are obviously jokes. In small towns, there are no gangs or "mental disorders" that's just ridiculous. I'm guessing it's A but I'm not *100%* sure. 3. Becaue alcohol dilates blood vessels, a person who goes outside in …

Hi.. I having trouble answering this question. Any input would be greatly appreciated =) Explain why the size of red blood cells stored in 0.15M urea would differ significantly from cells stored in the same concentration 0.15M of Na Cl? (Hint: work out the osmolarity and tonicity of the 2 solutions and compare each solution to the intracellular fluid of the erythrocyte(Red blood cells) This is what I done so far... not sure whether it's right or not. Osmolarity Urea: 0.15 x 1000 = 150mOsM Salt [Na Cl]: 0.15 x 2 (the sodium and the chloride ions dissociate and 2 particles formed) x 1000 = 300 mOsM Tonicity Urea: cell bigger (swell) and becomes normal…

Can anyone give me a definition of Elements, Ion and molecule? Are they related? thanks

I have a math project which consists of building a bridge, and I have to make a complete report of how I carefully planned how wires, poles, etc. would be able to handle the weight. So I need to know how to calculate how much force a metal wire can handle according to whatever parameter (ray? material? length?) is involved. I'm talking about the pulling force on the end of the wire when the other end is attached. Thanks.

1. A condition in which fats build up in the liver and cannot be broken down. 2. A condition in which liver tissue is destroyed and replaced with useless scar tissue. I know that the two answers for above is fatty liver and cirrhosis. But I don't know which is which. It's so confusing. 3. Physical and mental impairment resulting from alcohol use. --> is this intoxication? 4. The KIDNEY oxidize(s) alcohol to form water, carbon dioxide, and energy. --> I'm pretty sure this is false because I think it's liver that does this. Help! I appreciate this greatly.

I was wondering if someone could help me with this word problem. I am terrible with word problems.....I need you to explain it in steps and tell me why you are doing what you are doing. I greatly appreciate it. Tom and Huck start a business painting fences. They paint Aunt polly's fence and find that they can paint a 200 square foot fence in 40 minutes if they work together/ If huck works 4 times faster than tom, how long would it take each of them to paint a 500 square ft fence working alone?

Okay, I have a question that I need to get my mind straight to this. I'm still kinda confused about it. Check this out, these a-m letters are supposed to fix the word equations (or "balances?"), these in pencil I wrote from the whiteboard. These in black, I put it in what was missing, led to my belief/thought on this. I'm not sure if these are correct.....and plus, check this out on a), it was written by a teacher (i put / on number 2, btw, cuz me and teacher were discussing on it on somethin)...the teacher says his on a) is 100% right and i'm not sure.....because i think Nsmall2+2Hsmall2>2NHsmall2 was supposed to be like Nsmall2+Hsmall2>2NHsmall2.......the compound…

Was wondering if anyone could tell me how I'd go about integrating: Int[(r(z))^2 dz] on the interval [1,h] where r(z) is an arbitrary function of z. help is appreciated:)

Hi. I was wondering if any of you could tell me the term used to keep cells alive but stop them growing when they are removed from the host (by altering the growth medium). This is in relation to Dolly the Sheep if that helps at all. Any help would be greatly appreciated! Thanks

Hullo, I am a 16-year-old. This is a question in my assignment. A student said that a piece of paper would fall on the ground when released because the atmospheric pressure forced the paper to fall down. Use the kinetic theory to determine whether the above statement is true. So my answer is (Pardon my grammar. i know it's bad) The above statement is false. The volume of fixed mass of air on the upper and lower sufaces of the paper is the same. This means that the number of air molecules moving around per unit volume of space is the same on the top of and below the paper. The frequency of collision between air molecules and the two surfaces of the piece of pa…

Hi, I'm really stuck on my biology homework. I need to find any plant (excluding a cactus), a picture of it and list at least 6 adaptations of it. Can anybody help?

hello... please help me with this question. thanks. A small block of mass 2 kg is held against the side of a larger block of mass 10 kg which sits on a frictionless floor. The small block does not touch the floor and does not slip down as the blocks move across the floor. The coefficient of static friction between the two blocks is 0.4. The smallest acceleration the two blocks can have is a) 2.5 m/s2 b)4.9 m/s2 c) 5.4 m/s2 d) 9.8 m/s2

I'm starting a Complex Analysis class at my high school and I'm having trouble proving this delta-epsilon limit: [math]\lim_{z \to 0} \frac{\overline{z}^2}{z}=0[/math] any suggestions?

I`m trying to prove the following: An algebraically closed field is of infinite extension over its prime subfield. I'm not sure I translated it correctly. What I mean is: Let K be an algebraically closed field and k its prime subfield. Then the degree of the extension K/k is infinite, i.e. [K:k] is not finite. I have in my mind an example like C/Q (the complex and rational number fields). I know it's true in this case, because Q has transcendental numbers. So I tried to prove k must have a transcendental element, since if the extension were finite, it would be algebraic. But I`m not sure this would work, because not all infinite extensions are algebraic. In a…

Hello there, I am a student studying in th UK, i am 15 years old and recieved news the other week of beig invited to a science masterclass in Iceland. Today i recieved my letter from the organisation that is organising it, amongst this i found that some work had to be submitted to enable me to go iceland on this oppertunity of a lifetime trip. I was given a short article telling me that, "a young boy is confused about reporters saying that global warming is caused by Humans, but he would like to know wether it is created by humans or is it a natural occurance" So in a summary i need the following to be observed: Who do you feel is causing it What has caused it …

Hi everyone, This is my first post on this forum which I stumbled across while searching for physics help on google. Anyway Im going to try to make this short. Im taking grade 12 physics and so far we are doing review and I remember nothing. Om going to post a few questions and hopefully you can give me specific break down on how to do it. Ill give it a shot and post my solution or if Im unable to do it, ill ask for your help. PS I would really appreciate you guys giving me a general way of approachign these questions that makes it easy for me to determine what Im looking for and the shortest way to get there. Well here are the questions 1) A basketball is thrown…

Hey sorry this isn't particualy sciencey, but i need your help. I'm doing my German A level coursework on Einstein and i really need people opinions of him. so please could you let me know what you know about him, your opinion on him, It doesnt have to be just about his scientific side. thank you

Hi I have just conducted a test for fats using gresase spot test at biology class. But I don't quite understand why will the translucent spot (cooking oil) disapear after immersing into organic solvent. The test procedure: 1. Transfer a drop of cooking oil to a filter paper and let it dry in the air for 5 minutes. 2.Hold up the filter paper to light and observe any translucent spot. 3.Immerse the filter paper into an organic solvent. Take it out and let it dry. 4.Examine the filter paper against light again. Note any change in the filterpaper. Use egg white solution and distilled water as controls. thanks in advance.

A planet with an atmosphere entirely consisting of O2 and atomic oxygen, O, is exposed to solar EUV radiation at a wavelength of λ = 80 nm. The O2 does not absorb this radiation but the atomic oxygen is ionized by it with an absorption and ionization cross section of σ = 1x10-18 cm2. The O+ ions rapidly undergo charge exchange with O2 to form O2+ ions, and the only electron and ion loss process is dissociative recombination of the O2+ ions O2+ e→O+O k1 = 1x10-8 cm3 s-1 If the solar flux is 1x10^11 photons cm-2 s-1 at 80 nm, the atomic oxygen scale height is 50 km and the O density is 1.6x10^12 cm-3 at 100 km, calculate the peak electron density of the resulting ionosph…

What are the reasons for why high blood pressure is a health concern?