Homework Help

I simply cannot get this question correct and I am not sure where I am going wrong. Any help or advice would be much appreciated. -Andrew

I have to do a wordpress blog for college which could do with a few comments if ye could be so kind. It'll probably be deleted once it is marked. http://cit-blogs.com/R00129674/

so im taking a quiz and im having difficulty answering an odds ratio question. this is it.... Of 576 osteoporosis patients, 256 had a history of corticosteroid use. Of the 800 controls, 250 had a history of corticosteroid use. doing the work i got (256)(800)/(576)(250)= (204,800)/(144,000)= 1.42 but when i entered it it was considered wrong? i want to know if someone can help me with what i calculated wrong?

So I have to figure balance this equation. _P +_O2 ---->__P2O5 Here is my work so far; 2P +_O2 ---->__P2O5 P=1 2 P=2 O=2 O=5 But now I am stuck trying to figure out how to get 5 oxygen on the reaction side. I was thinking 2.5, but is it possible to have decimals in the coefficient? Thanks in advance.

Hello guys, Not sure which forum is best to post this, but I have a question in mind: as a student, what would be the best job in which you can read book? not necessarily study, but reading is enough. what do you think? intuitively I thought of working for uni library, but what would be needed in there? its either putting back books to the shelves or being in the IT team for trouble shooting, which doesnt fit lol I havent tried working at uni lib though, so I cant judge

Hello! I think the answer is E? pls help You are studying the effects of tomato hornworms (herbivores) on tomato plants in a laboratory experiment. Tomato plants have trichome defenses (small hairs) and chemical defenses (called “inhibitors”) that interfere with digestion by the herbivore. From your experiments, you discover that the number of trichomes on leaves is unchanged after feeding by hornworms whereas the concentration of “inhibitors” increases. From this experiment you can conclude that A tomatoes must have other defenses in addition to trichomes and “inhibitors”. B there has b…

Which of the following are consumers? Choose all that apply. I have chosen all of them but the plants because they are producers? I am not too sure on the prey option very vague I think what kind of prey? It could be a rabbit, which is a consumer of plants. OR does it mean consumers in this context? That would include only predator, herbivore, parasite only. pls help Predator Herbivore Prey Parasite Host Plant

This is for a school project and I am in Year 7. I would like to know anything to do with these questions because I would be very interested to find out

About TLC (curiosity) So we do a lot of TLC analysis as well as melting point testing in my organic chemistry class this year. The reason I am asking more in depth on TLC is I get the concept of TLC. You use a board and solvent to extract and confirm purity of a polar substance based on the resulting Rf values. This makes sense to me through and through. My curiosity is that I want to understand better the intricate workings of this. I am not good enough to look at the molecular structures of say for example Naphthalene, Benzoic Acid, Aspirin, Caffeine etc. and say ok out of these 5 the order should ideally be (X,Y,Z…) I believe this stems from my lack of gras…

I'm a little confused by what these equations are saying: ∆d = 2t (phase shift for neither or both waves) ∆d = 2t + 0.5 * wavelength (phase shift for only one wave) ∆d = m*wavelength (constructive) ∆d = (m + 0.5)*wavelength (destructive) I think t is the thickness of the film, but then what is ∆d?

For some reason I just literally can not figure this out, my brain has hit a wall even though I know it's so simple... So I have 25,000mg of binder and I have 250mg of active ingredient. All I need to know is what is the ratio, how do I figure out how much active ingredient is in x amount. Lets assume I wanted like 3 mg worth of active ingredient, how much would I have to scoop from the mixture to get that?

I was reading how methane is extracted from methanol. I came across two reactions. Please complete them for me. a) CH3OH + ZnCl2 + HCl -----------> b) CH3Cl + LiAlH4 -----------------> I don' t know how to complete such reactions. Please help.

I have an upcoming test on Monday. Our teacher is notorious for giving big tests (note, I am in high school and the tests he gives have nearly a hundred questions!). My last two tests, all Chemistry based, I scored a 60% on one and a 65% on the other. This will be my last Chemistry test for this year and I want to make sure my percentage goes up. Any advice for creating better study habits? Whenever I actually get down to study I end up losing focus. Any and all help appreciated.

Hi, I apologise if I am posting in the wrong forum. I'm interested in the history of the telecommunication, so radio, the telegraph, etc. Can anyone recommend any good books or other resources? Thanks.

The answer is listed as A. How do fish concentrate their cells? How does concentrating their cells prevent loss of fluid? Does anybody know of any resources where I can read more about this? Thank you

Hello, I am an engineering student and I have to calculate something. I am locked in a situation and I don't know how to solve it or if it is correct. The problem: We have a steel structure that is welded together. It consists of 4 beams which are welded together. On the upper beam there is a load of 40 kg (=400 N), the lower beam is supported by a cylinder which gives a normal force (40kg = 400 N). How I solved: I made a free body diagram of each beam (4 beams). Each beam is clamped on both sides, so we get a hyperstatic structure. I started calculating with the upper beam, which is symmetric loaded which made the calculation of the unkown possible…

This is for a school project and I am in Year 7... I would like to know any facts about my questions as I would be very interested to find out

Okay, so I'm trying to work out the effect of substrate concentration on reaction velocity. I did an assay, using PNPG in varying concentrations. I then need to work out the reaction rates in order to graphically determine the Km and Vmax for each reaction. So, my results are: (volume of PNPG & absorbance reading) 0.1 (PNPG) = 0.078 (absorbance) 0.2 = 0.124 0.3 = 0.268 0.4 = 0.315 0.6 = 0.507 0.8 = 0.632 1.2 = 0.724 To convert into concentration, I used the Beer-Lambert law. I had already calculated the conversion factor, of 333.3, from a previous experiment. This gave me concentrations of: 25.997 79.992 89.324 104.990 168.983 210.646 241.309 I need to know how t…

// the question is about methodOverloading in java. I am having trouble with this method, i only included this one method as the others are working fine // i test this code with the string "the cat sat on the mat" "1" "12" "a" "m" //the method should remove all characters beteen the given characters(exclusive) from the string. this should happen between the first instance of the first character and the last instance of the second character. // with the string "the cat sat on the mat" this method should print out "the camat" import java.util.Scanner; public class methodOverloading { public static void main (String [] args) { Scanner scan = new Sca…

Hello guys, If we have a flow with Temperature distribution. There is a hot object around which there is flow. to find if the flow is laminar or turbulent, should we consider an average viscosity or should we consider the viscosity around the object? I feel it is safer to assume the lowest viscosity because it can tell us if the flow around the object is laminar or turbulent. what do you think? should this be done? does the low temperature away from the object matter? (lets say viscosity is 10^-3 away from the object and 4X10^-4 neaer the hot object)

I was recently reading a topic about: What if gravity acted like magnetism? While I was studying about it, I come across the information which makes me little blunt about basic information. My questions arise when I read "If you have a positive charge the first thing it does is repeal all the other positive charges around it and attract all the negative charges." I this happens because of magnetism and the electric force? Is that true that they tend to cancel themselves out? And if its true than what is the reason behind it?

I am a ninth class student. Our teacher explained the topic of molecules in the class. CO2 Molecule is stable and CO3 is charged. But why CO is stable? please explain.

crest is 12 of a wavelength. find wavelength,time period, frequency and velocity.

Hello, I am having trouble answering this question from biomolecules unit lecturer at university: "If you used 1 microgram human genomic DNA for PCR amplification of 350 bp fragment of ALDH2 gene, after 30 cycles of PCR reaction, how much of the PCR products (in weight) should be yield if all the reagents are not exhausted and the PCR reaction is not saturated?" I know how to calculate copy number using the equation "number of copies = ( amount * 6.022x1023) / (length * 1x109 * 650)", but i'm not sure whether that equation is what I need to use here? I'm guessing the variables I have as options to put into an equation are: 1 microgram of DNA (or 1000 nanogram…

Answer this question please