Thursday

May 28, 2015

May 28, 2015

Total # Posts: 21,069

**Biology/medicine**

Please give subject instead of Stuck, help. A math teacher can not help much.
*November 14, 2014*

**MATH!!!**

P = 2*L + 2*W (1,7) --> 2*1 + 2*7 = 2+14 = 16 (7,6) --> 2*7 + 2*6 = 14 + 12 = 26 etc if you want 12 pick an L, say 4 2*4 + 2*w = 12 4 + w = 6 w = 2 so (4,2)
*November 14, 2014*

**physics**

No, it is already at 100, the boiling point You want .020 kg * Heat of Vaporization of water in Joules/ kg so .020 kg * 2.26*10^6 J/kg
*November 14, 2014*

**Science 8 - Check Answers**

You are welcome.
*November 14, 2014*

**Science 8 - Check Answers**

4. OK, but if I had the choice I would say "mechanical" energy 5. I do not think so. You want a poor conductor for an "insulator". For a resistance you usually use a reasonable conductor but make it thin.
*November 14, 2014*

**history essay please help!**

Ok, good luck :) I think if you just want to compare populations you should say: The world population is much larger than it was a hundred years ago due to: The things you mentioned. Do not get into growth or growth rate because that is mathematics of exponential functions.
*November 14, 2014*

**history essay please help!**

The population has doubled many, many times, and even right now the world's population is still skyrocketing. ------------------------------- The essay is about growth today versus growth 100 years ago. The population has doubled many times since when? 100 years ago? 1 ...
*November 14, 2014*

**Physics**

see: http://www.gocomics.com/tarzan?ref=comics
*November 14, 2014*

**Physics**

Fcentripetal = mAc = m v^2/R = m (7.2)^2/8.2 Fgravity = m g = m (9.81) so total force on vine = m ( 9.81 + 7.2^2/8.2) = 10^3 Newtons solve for m Note: Tarzan just swam across the wild river from rock to rock with a vine around his waist and the natives are rebuilding their ...
*November 14, 2014*

**Math**

(3/(5/4)) (4/5) = 12/5 * 4/5 = 48/25 which is about 2
*November 13, 2014*

**Math help please!!!!!!**

assuming that the origin is your center of dilation, B is correct.
*November 13, 2014*

**Algebra**

agree with Steve but most importantly look how he did it. It is not necessary to multiply the whole thing out, just the terms that end up being in x^3
*November 13, 2014*

**maths**

today
*November 13, 2014*

**calculus**

F' = 10 x^-2 dx - 2 x^-6 dx F = -10x^-1 + (2/5) x^-5 + c when x = 1 , F = 0 0 = -10 + 2/5 + c c = 48/5 F = -10 /x + 2/(5x^5) +48/5
*November 12, 2014*

**Physics**

Forget the formulas, think !!!!
*November 12, 2014*

**Physics**

I will try crate 1 m = 30 kg F = 100 N 1. impulse = F t = 100 * 3 = 300 Ns yes 2. Force = change in momentum/time and initial momentum = 0 so 100 = change in momentum/3 so change in momentum = 300 kg m/s = Ns (by the way if there is a difference between change of momentum and ...
*November 12, 2014*

**St Ans School**

or sketch a number line. You will see that the middle between 75 and 45 is 15 each way. or take the average (75+45)/2
*November 12, 2014*

**Physics**

150 v = 4.5 * 10 = 45 v = .3 m/s t to get back = 100/.3 = 333 seconds we have five min which is 300 seconds things do not look good :( Better throw that camera harder.
*November 12, 2014*

**physics**

angular momentum I omega does not change. If I decreases, omega increases to keep the product constant (the spinning skater pulling her arms in problem :)
*November 11, 2014*

**Math**

distance = rate * time = r t = 17 * 4
*November 11, 2014*

**English**

He wants (singular) They WANT (plural) Police is they, not he.
*November 11, 2014*

**chemistry**

that is the opposite of cloning
*November 11, 2014*

**chemistry**

I said that MIXING male and female genes ...... hastens evolution
*November 11, 2014*

**chemistry**

I can see how it might be nice to have genetically identical subjects in a lab experiment, but not in the real world. If the prototype happened to be allergic to some chemical that became common a hundred years from now, that would be unfortunate!
*November 11, 2014*

**chemistry**

It says that cloning does not allow adaptation. We need to adapt. That is what evolution is about. There is no mixing of genes in cloning. Each generation is identical to the prototype. That is a very rigid way to propagate a species, even if the prototype is Superman :)
*November 11, 2014*

**chemistry**

The problem with cloning is that mixing characteristics of male and female in the next generation increases diversity of the gene pool and hastens evolution of species to survive a changing environment.
*November 11, 2014*

**Is this right**

as far as I know
*November 11, 2014*

**Is this right**

sin (cos - sin) + cos (sin + cos) -sin^2+cos^2 + 2 sin cos I have cos^2 You have cos
*November 11, 2014*

**math**

8*6 = 48 slices total 48/24 = 2 slices each person 2/6 = 1/3 of a pie each to check 24 people * 1/3 pies/person = 8 pies sure enough :)
*November 11, 2014*

**Financing and Budget**

Yes, C
*November 11, 2014*

**Chemistry**

hard to argue with any of those
*November 11, 2014*

**Algebra Help URGENT Please?**

380/.2 = 3800/2 = 1900
*November 11, 2014*

**Algebra Help URGENT Please?**

95 + .2 s = 475 .2 s = 380 s = 380/.2
*November 11, 2014*

**Math**

yes side , side , side
*November 11, 2014*

**World History Answer Check**

That is more complete. Of course it does not cover the average dead French citizen.
*November 11, 2014*

**Algebra help URGENT Please?**

Oh, sorry, thought there were five eaters, there are 6 25/6 = about 4
*November 11, 2014*

**Algebra help URGENT Please?**

.1*124 =12.4 so.2*124 is about 25 25/5 = $5
*November 11, 2014*

**math**

what does the comma mean in F(x, y) = y cos x − xy sin x, xy + x cos x ? are we to integrate F around the perimeter of the triangle by integrating the divergence over the area or what ? Look at earlier questions below.
*November 11, 2014*

**Math**

the three sides of triangle 1 are the same length as the tree sides of triangle 2
*November 11, 2014*

**Math**

side EF = sqrt (4+4) = sqrt (8) side FD = sqrt (1+4) = sqrt 5
*November 11, 2014*

**Math**

hey if all three sides are the same it is congruent by side,side,
*November 11, 2014*

**Math**

side AB = sqrt (16+1) = sqrt 17 side BC = sqrt (4+4) = sqrt 8 side CA = sqrt (1+4) = sqrt 5 side DE = sqrt (16+1) = sqrt 17 LOL I guess you get the SSS idea
*November 11, 2014*

**Calculus**

Look at that link. It gives you the series expansion about zero explicitly.
*November 11, 2014*

**physics**

the charge on a proton is equal in magnitude and opposite in sign to the charge on a electron. Therefore if an atom has the same number of electrons as it has protons, it is neutral. Otherwise it is called an "ion".
*November 11, 2014*

**Physics**

c) (1/2) m v^2 = answer to b d) The reason they want is that the person would have reached terminal velocity where air drag up = weight down before falling 5000 meters. The reason they forgot about is that the diver also has the constant horizontal velocity of the airplane the...
*November 11, 2014*

**Did I get this right?**

yes, correct but perhaps you better multiply out and collect like terms for example 3x^2 + x^2 = 4 x^2
*November 11, 2014*

**physics**

weight = .010*9.8 = .098 Newtons x = .05 m k = 1.96 N/m omega = sqrt (k/m) = 2 pi f so f = 2.23 T = 1/f = .45 seconds
*November 11, 2014*

**Derivatives**

for starters x^3[ 4(5x-1)^3 (5) ] + 3 x^2 (5x-1)^4
*November 11, 2014*

**Square Roots**

11^2 = 121 12^2 = 144
*November 11, 2014*

**math**

yes, that makes sense. Did she get 26 ( 50/2 + 2/2 = 25+1 = 26 or did she come up with something else entirely?
*November 11, 2014*

**World History Answer Check (Ms. Sue)**

I like your other answers.
*November 11, 2014*

**World History Answer Check (Ms. Sue)**

2. What was the effect of total war on ordinary citizens during World War I? A: Because of total war, ordinary citizens underwent rationing of goods. =================================== True in the world outside the war zone, such as in the US. However ordinary French or ...
*November 11, 2014*

**Math**

I do not know what power you are raising twelve to if you mean 2 + (12)^2 then 2 + 144 = 146
*November 11, 2014*

**physics**

I need to know how far the center of mass of a blade is from the axis. If we assume the blade is a uniform rod with cg at its center (unlikely) then the moment of inertia about its end is: I = (1/3) m L^2 so for 3 we have just I = 1 m L^2 = 159 * 3.69^2 = 2165 kg m^2
*November 11, 2014*

**Math**

200 n = 3000 2 n = 30 n = 15
*November 11, 2014*

**Physics**

u = horizontal velocity = 3.2 cos 40 forever Vi = initial up velocity component = 3.2 sin 40 v = Vi - 9.8 t h = 1.175 + Vi t - 4.9 t^2 at ground, h = 0 so 4.9 t^2 - Vi t - 1.175 = 0 solve quadratic for t, use positive solution then range = u t
*November 11, 2014*

**Statistics**

well, just using what iss given and assuming it is true probability that woman uses computer at work = .72 so probability not = 1-.72 = .28 Binomial distribution prob 5/5 yes = C(5,5) .72^5 *.28^0 = 1 * .72^5 * 1 = .72^5 = .193 (second answer) so prob that someone does not = 1...
*November 11, 2014*

**physics**

seesaw :) 1 x = 35.5(1.27*10^-10 - x) 36.5 x = 45.1 * 10^-10 x = 1.24 * 10^-10 in other words right beside the Cl atom
*November 11, 2014*

**physics**

find the well depth in meters. I doubt if it is really just 10 cm deep but if really true then 0.10 meter multiply mass in kilograms by g, about 9.8 meters/second^2 to get weight force multiply that force by the depth to get work done.
*November 11, 2014*

**question**

I believe so.
*November 10, 2014*

**Math**

d = 4 t d + t = 20 5 t = 20 t = 4 d = 16 16-4 = 12
*November 10, 2014*

**Math help please!!!!!**

24/10 = 30/x 24 x = 300 x = 12.5 I am assuming that x and 10 are along the wall and not the ground.
*November 10, 2014*

**PHYSICS**

dW = p A dr dW = p 4 pi r^2 dr integrate W = p (4/3) pi (r final^3 - r initial^3) W = p (final volume - initial volume)
*November 10, 2014*

**Trigonometry**

sin^-1 (1.2 /4.4 )
*November 9, 2014*

**Physics**

F = m a 150 lbs = 68 kg Fscale up - m g down = m a Fscale up = m g + m a = 150 pounds + 68* 10 newtons = 150 pounds + 680 Newtons 680 Newtons = 153 pounds so 150 + 153 is about 300 pounds
*November 9, 2014*

**math**

65/60 is to the right of 1 on a number line. The result is positive. +
*November 9, 2014*

**Physics**

Thanks, I just went and looked, might do that but I am pretty busy here when I am not coaching our sailing team or whatever.
*November 9, 2014*

**Physics**

I will go look though.
*November 9, 2014*

**Physics**

I am a retired professor, do this for fun.
*November 9, 2014*

**Physics**

You are welcome.
*November 9, 2014*

**Physics**

Ah, here: http://earthsky.org/earth/tides-and-the-pull-of-the-moon-and-sun ( former clammer and lobsterman here :)
*November 9, 2014*

**Physics**

maximum high and low tides occur when the earth, moon and sun are co-linear. That is at full moon and new moon. Such tides are called "spring tides" and occur about twice a month.
*November 9, 2014*

**Physics**

Yes 0 free falling weightless :)
*November 9, 2014*

**Physics**

Backup link :) http://www.jiskha.com/display.cgi?id=1282164495
*November 9, 2014*

**Physics**

Like - "weightless" :)
*November 9, 2014*

**Physics**

No !!! ZERO no force on scale - in free fall, accelerating downward at 9.81 m/s^2
*November 9, 2014*

**Physics**

Total force on person = m g = m a in free fall. No external force on person from scale
*November 9, 2014*

**physics**

ke = .5 m v^2 + .5 I w^2 I = m r^2 w = v/r so ke = .5 m v^2 + .5 m r^2 v^2/r^2 ke = m v^2 v = 2.1 * 3.8 = 8.0 m/s so ke = 5.6 *64 Joules = m g h = 5.6 g h so 64 = g h h = 64/9.8 sin 17.7 = h/distance up ramp so distance up ramp = h.sin 17.7
*November 9, 2014*

**Physics**

see this similar reply http://www.jiskha.com/display.cgi?id=1415568126
*November 9, 2014*

**Chemistry**

How do you find the amount of water that reacted 2 mol of phenylmagesium bromine?
*November 9, 2014*

**Chemistry **

If there are 25 mg of water in a typical drop of water, how many drops of water would react completely with 2 mmol of phenylmagnesium bromide? How do I set up the problem?
*November 9, 2014*

**Physics**

sum of vectors, not product Pa =3.2[ 2.3 i + 4.2 j] = 7.36 i +13.44 j Pb =2.9[ -1.8 i +2.7 j] =-5.22 i +7.83 j P = (7.36-5.22) i +(13.44+7.83) j
*November 9, 2014*

**Physics**

initially p1 = 4 i + 2 j p2 = -3i + 3 j total p = 1 i + 5 j final p must be the same final p1 = px i + py j p2 = 6 i - 3 j px + 6 = 1 px = -5 vx = -5/2 = -2.5 py -3 = 5 vy = 5/2 = 2.5 so v = -2.5 i + 2.5 j
*November 9, 2014*

**physics**

no question was asked
*November 9, 2014*

**Physics**

m g h + (1/2)m v^2 = total energy = constant h is height above hanging straight down mg(2-2 cos 30)+.5m*9 = total energy = m g (2 -cos max angle when v = 0) notice m has nothing to do with this problem, cancels = mg(2-cos45) +.5 m v^2
*November 9, 2014*

**Physics**

Ke - work done against friction = (1/2)kx^2 (1/2)mv^2 - .3 m g (.2+x) = (1/2)(800)x^2 (1/2)*2*9 -.3*2*9.8(.2+x) = 400 x^2 solve quadratic for x why are you talking about m g h ??? it fell on horizontal plane?
*November 9, 2014*

**Math**

b did both draw Venn diagram fri---both- weekend |20-b | b |29-b| 20-b + b + 29-b = 40 49 - b = 40 b = 9 11 fri , 9 both , 20 weekend
*November 9, 2014*

**Calculus**

You are welcome.
*November 9, 2014*

**Calculus**

Do you mean? y= (x^3+8)/(x+2) ???? or what you typed? If my guess is correct then (bottom dtop/dx -top d bottom/dx)/bottom^2 =[(x+2)(3x^2)-(x^3+3)(1)]/(x+2)^2 =[3x^3+6x^2-x^3-3]/(x+2)^2 = (2x^3+6x^2-3)/(x+2)^2
*November 9, 2014*

**calc**

x y = 50 2 x + y = p 100/y + y = p dp/dy = 0 for min = -100/y^2 + 1 y = 10 x = 5 p = 20 feet of fence
*November 9, 2014*

**Algebra**

if x = 6 then f(x/2) = f(3) = 4 y = 4/2 = 2 (6,2)
*November 9, 2014*

**Algebra**

if x = 3 then f(x) = 4 so y = 4 + 4 = 8
*November 9, 2014*

**Physics, please!**

I used g = -10, you do it with your g
*November 8, 2014*

**Physics, please!**

I guess he kicked it horizontally? Hi = 22 0 = Hi - (1/2)(10) t^2 4.4 = t^2 t = 2.1 seconds goes 17 meters horizontal in 2.1 seconds u = 17/2.1 = 8.1 m/s
*November 8, 2014*

**Physics**

F = mu m g work = F d = mu m g d Ke lost = (1/2) m Vo^2 Vo^2 = 2 mu g d mu = Vo^2/(2gd)
*November 8, 2014*

**Algebra 2**

4x(x-6)-x(x-2)=-24 4 x^2 - 24 x - x^2 + 2 x + 24 = 0 3 x^2 -22 x + 24 = 0 18 and 4 I bet (3x - 4)(x - 6) ??? yes x = 4/3 or 6
*November 8, 2014*

**Algebra 2**

6 x^2 - 13 x + 6 = 0 we want 6 * 2 and a 1 to get 13 or 9 and 4 (3 x - 2)( 2x - 3 ) ah, 9 and 4 x = 2/3 or 3/2
*November 8, 2014*

**Algebra**

speed up = u -c speed down = u+c d = speed * time 3 = (u-c)1.5 3 = (u+c)1 1.5 u - 1.5 c = 3 1.5 u + 1.5 c = 4.5 --------------------- add 3 u = 7.5 u = 7.5/3 3 = 7.5/3 + c c = (9-7.5)/3 = 2.5/3 = .83333333333333333333333333
*November 8, 2014*

**S.S.**

Civil Rights Act of 1964? People are still discriminating against black people, particularly in the South
*November 8, 2014*

**Algebra 2**

we know that 7*7 = 49 and 49+1 = 50 so we know what to do 7 p^2 - 50 p + 7 = 0 (7 p - 1) ( p - 7) = 0
*November 8, 2014*