Tuesday
October 25, 2016

# Posts by -

Total # Posts: 87

mathematics
A group of twelve people are going to take a ride on a roller coaster at the same time in two different trains, one of which cannot fit more than 8 passengers, and the other cannot fit more than 7. In how many ways can the group take a ride?
May 6, 2016

chemistry
In an experiment, 95.0 mL of 0.225 M silver nitrate was mixed rapidly with 47.5 mL of 0.225 M calcium chloride in a coffee cup calorimeter. If a reaction occurred, was it exothermic or endothermic? If the reaction started at 23.7 °C, what is the final temperature of the ...
April 22, 2016

Spanish
were they right?
January 14, 2016

AP Physics
A centrifuge rotor rotating at 12000 rpm is shut off and is eventually brought to rest by a frictional torque of 1.50 m·N. If the mass of the rotor is 4.80 kg and it can be approximated as a solid cylinder of radius 0.0710 m, through how many revolutions will the rotor ...
January 6, 2016

AP Physics
How fast (in rpm) must a centrifuge rotate if a particle 6.0 cm from the axis of rotation is to experience an acceleration of 130000 g's
December 4, 2015

AP Physics
The Eiffel Tower is 300 m tall. When you are standing at a certain place in Paris, it subtends an angle of 7.0°. How far are you, then, from the Eiffel Tower?
December 3, 2015

AP Physics
What is the minimum work needed to push a 1025 kg car 290 m up a 17.5° incline with zero friction?
November 11, 2015

AP Physics
sorry 8.0*10^4 J of work
November 11, 2015

AP Physics
A car does 8.0 ✕ 104 J of work in traveling 2.7 km at constant speed. What was the average retarding force (from all sources) acting on the car?
November 11, 2015

math
now all you have to do is find the number from the steps above that has the tens digit as twice the ones digit
November 11, 2015

math
if the sum of the numbers is 9, then it must be a multiple of 9 now what are all the 2 digit multiples of 9?
November 11, 2015

Math
^ that is actually wrong, because you are getting 4 marbles out of the bag...
November 10, 2015

Physics
To answer this question you must first solve: Acceleration=(gravity)(coefficient of friction) which equals 3.724 you than plug acceleration into the equation (velocity final)^2=(velocity initial)^2+2(acceleration)(distance) and you solve for velocity initial: (0)^2=(VI)^2+2(-3...
November 1, 2015

algebra
well I always start by drawing a small diagram just to help you visualize. you can see that you need to set a proportion of Rogers height Poles height _____________ = ______________ Rogers shadow Poles shadow 5 P _ = __ 3.5 15 now you can cross multiply 5(15)=3.5(P) 75=3.5P P...
November 1, 2015

physics 11
how did you fins 41.5??
October 20, 2015

Art.
Lamp was correct, 5 is A.
March 10, 2015

language art
I think A. But I'm not sure
January 9, 2015

math
let the width of the rectangle be k. so the length of rectangle is (3/2)k. Perimeter of the rectangle=(3/2)k+(3/2)k+k+k =5k =180m so, 5k=180 k=36. thus, the width of the rectangle is 36m. For the length, Length=(3/2)(36) =54m
September 10, 2014

Grammar
some ideas for thought: 1.education-to get a better job and future 2.knowledge-open our eyes to see the world in another light and gain insights of how things work. 3.Appreciation of knowledge 4.Make new friends 5.An alternative of home
September 10, 2014

Grammar
is it an essay?
September 10, 2014

math
1)1-1 and 4 (i can only think of this) 2)1-2 and 2
September 10, 2014

physics
Assumption: no air resistance. Since the downwards direction is stated as negative, acceleration due to gravity is -10m/s2. using a=(v-u)/t, a being -10, u being initial velocity, v as velocity when hits the ground, t as time, u get t=(3.9-v)/10. find another value of such ...
September 9, 2014

MATHS
multiply sign
March 20, 2014

MATHS
WHAT IS 32X14+_=689
March 20, 2014

CHEMistry
MOLES=MASS/MR
March 20, 2014

social justice
what is the difference in older forms of corporate censorship and how it looks today?
October 1, 2013

social justice
how though? i need help!
October 1, 2013

social justice
how do you think globalization relates to the kind of large multinational corporations?
October 1, 2013

social justice
What is the fundamental difference between lifestyle branding and past forms of branding?
October 1, 2013

English
Submitted it and got it right, thank you ma'am. :)
October 8, 2012

English
I'll take each answer and show you why I think it is right, or why I think it is wrong. "He has skin that is rough and burned by the sun." This answer is completely irrelevant and is trying to throw me off course. "He is cruel and feels no compassion for the...
October 8, 2012

English
4. Read the following passage from “The People Could Fly”: The slaves labored in the fields from sunup to sundown. The owner of the slaves callin himself their Master. Say he was a hard lump of clay. A hard, glinty coal. A hard rock pile, wouldn’t be moved. What...
October 8, 2012

English
1. Which sentence describes setting? As much as it saddened her, the first thing Nan had to do was leave her beloved family home. Marcy wanted to go to the dance, but Rob’s treatment of her that day gave her second thoughts. Steve was fairly short, with glasses and dark ...
October 8, 2012

english 1
"To help prevent pollution, people could walk, ride bikes, and use public transportation."
October 8, 2012

lang arts
The correct answers are: 1. D 2. A 3. B 4. B The kid above was wrong with number 1.
August 31, 2012

math
four of every seven teenagers would prefer to watch a comedy when going to the movies
August 20, 2012

physics
the velocity of the water jet discharging from the orifice can be obtained from v = (2gh)^(1/2), where h = 2m is the depth of the orifice from the free water surface. determine the time for a particle of water leaving the orifice to reach point B and the horizontal distance x ...
April 3, 2011

chemistry
4.76 atm
January 31, 2011

Trigonometry
Solve for x: 1. 2sin(2x)+cos(x)=0 2. cos(2x)=-2sin(x) 3. tan(x)=2sin(x)
April 21, 2010

OPERATING SYSTEM
February 10, 2010

calculus
Deternime the instantaneous rate of change at x=2 for: y=x-2x^3
February 9, 2010

math
Estimate the instantaneous rate of change for x=2 for y=x y=x^2 y=7
February 9, 2010

math
Estimate the instantaneous rate of change for x=2 for y=x y=x^2 y=7
February 9, 2010

Physics
I DON'T KNOW
February 6, 2010

math pls
Tidal forces are greatest when the Eaetg, the sun and the moon are in line. When this occurs at the Annapolis Tidal Generating Station, the waterhas a maximum depth of 9.6 m at 4:30 pm and a minimum depthof 0.4 m 6.2 hourslater. the equation is: y= 4.6cos (2pi/12.4) (t-4.5) + ...
January 26, 2010

solve (sq.rt 2) (tanx)(cosx) = tanx
January 26, 2010

math
solve 2.84 = (1 + x ) ^ 12
January 23, 2010

Hamlet
Something is rotten in the state of Denmark. (I.iv.90) Using two different literary devices, prove or refute the quotation above.
November 30, 2009

How bright a star appears can depend on how much light the star actually emits and how far away it is. The stellar magnitude scale can be adjusted to account for distance as follows: M2-M1 = log (b1 / b2) Here, M refers to a star's absolute magnitude, that is, how brightly...
November 30, 2009

The vertical position, h, in metres, of a gondola on a Ferris wheel is modelled using the function h = 10 sin ((pi/15) (t-d)) + 12 where t is the time, in seconds. The gondola must assume a vertical position of 7 m at t=0 s , and be on its way upward. Determine the phase shift...
November 20, 2009

Math
The height, h, in metres, above the ground of a rider on a Ferris wheel can be modelled by the equation: h= 10 sin ((pi/15 t) - 7.5) + 12 where t is the time, in seconds. At t=0, the rider is at the lowest point. Determine the first two times that the rider is 20 m above the ...
November 16, 2009

math
Solve 3sin2x - 1 = 0 Interval: [0, 2 pi] Solve 6cos^2x + 5cosx - 6 = 0
November 15, 2009

Solve 2tan^2x + 1 = 0 Interval : [0, 2 pi]
November 15, 2009

Determine approximate solutions for this equation in the interval x is all real numbers [0, 2pi), to the nearest hundredth of a radian: cosx + 0.75 = 0
November 13, 2009

math
A painted dot on the circumference of the wheel is 12cm from the centre of rotation of the wheel. How far does the dot travel in 5 sec., to one decimal place?
November 9, 2009

Show that tanx = sinx / cosx can be written as tan(x+y) = (tanx + tany) / (1 - tanxtany)
November 8, 2009

The manufacturer of a propeller for a small aircraft mandates a maximum operating angular velocity of 300 rad/s. Determine whether it is safe to install this propeller on an aircraft whose engine is expected to run at a maximum of 2800 rpm.
November 8, 2009

trigonometry
What is the exact value for sin5pi / 12 ?
November 8, 2009

Prove that: 2sinxsiny = cos(x-y) - cos(x+y)
November 8, 2009

Show that tanx= (sinx/ cosx) can be written as: tan(x-y) = (tanx - tany) / (1+ tanxtany)
November 7, 2009

math
The London Eye is a large ferris wheel. Each sealed and air-conditioned passenger capsule holds about 25 passengers. The diameter of the wheel is 135 m, and the wheel takes about half an hour to complete one revolution. a) Determine the exact angle, in radians, that a ...
November 6, 2009

MATH!
You would multiply the top one by -4 and the bottom one by +3, if you want to keep y positive.
October 19, 2009

Nucleus, Cell membrane/wall or cytoskeleton (depends on what you learned in class, or your text book). I'm not sure of the last one.
October 19, 2009

Spanish 3
Continued Tenía una pequeña carrera de la película. Estaba en películas múltiples, pero me jugué siempre. Mori en el 8 de abril, 1873 cuando yo y la segunda esposa, Jacqueline, recibían un partido de cena. mis palabras pasadas ...
October 19, 2009

Spanish 3
En el próximo ano, mi amigo Soler y yo publicamos una revista se llama “Arte Joven” que se ilustré. En este tiempo tenía muchas novias, junto con una esposa o dos. También en este tiempo, mis pintores grises y azules. Se llamó me...
October 19, 2009

Spanish 3
Continued : En el año 1900, viajé a París y me encantó! Viví con mi amigo Max. Max durmió en la noche y trabajó en el día y yo dormí en el día y trabajé en la noche. Era como la vida solamente. &...
October 19, 2009

Spanish 3
Would someone be willing to proofread my essay? It's supposed to be from the point of view of Pablo Picasso. Yo nací el 25 de octubre, 1881, en Malaga, Andalucia. Mi padre fue un pintor y un profesor de arte. Me enseñó los fundamentos de arte. Cuando ...
October 19, 2009

Biology
In a double-stranded fragment of DNA, which of the base pairs would you expect to be most stable
October 12, 2009

Chem
For the reaction I_2(s)+Cl_2(g) ==> 2ICl(g) ÄH= 36kJ, ÄS= 158.8J/K at 25° C. Calculate the temperature at which Keq is 4.0*10^3. ÄG= ÄH- TÄS = 36 - (298)(0.1588) = -11.32 ÄG= -RTlnK -11.32= -8.31Tln(4*10^3) -11.32= -6892.35 T T= .00164 ...
August 10, 2009

can you explain that better? i'm confused.
March 9, 2009

chem- easy
What is the total mass of a solution prepared by dissolving 4.00 of in 1.00 of water?
February 10, 2009

CHEM-vaporization
A 50.0g piece of iron an 152°C is dropped into 20.0g H2O(l) at 89°C in an open, thermally insulated container. How much water would you expect to vaporize, assuming no water splashes out? The specific heats of iron and water are 0.45 and 4.21 respectively, and Ä...
February 6, 2009

CHEMISTRY!
I did it again this time I got 7774.51g which is much better. Thanks alot!
January 27, 2009

CHEMISTRY!
I feel like I have made a mistake because the mass seems too small. I don't know where I went wrong :S Molality = ÄTf / (Kf * i) = 23.3°C / (1.86°C/m * 3) = 4.18m (mol C2H6O2 / kg water) The amount to dissolve is: n_C2H6O2 = molality * m_water = 4.18 mol/kg * ...
January 27, 2009

CHEMISTRY!
what mass of ethylene glycol C2H6O2 the main component of anitfreeze, must be added to 10.0L water to produce a solution for use in a car's radiator that freezes at -23.3°C. Assume the density for water is exactly 1 g/m.L
January 27, 2009

find points on the curve x^2+xy+y^2=7 (a) where the tangen is parallel to the x-axis and (b) wehre the tangent is parallel to athe y-axis. (in this case, dy/dx is not defined, but dx/dy is. what value does dx/dy have at these point?)
October 19, 2008

government
Advocates of a parliamentary system argue that congress is inefficient, moves slowly, and develops policies laced with compromises. What evidence exists to support this negative evaluation?
October 19, 2008

thank alot
October 19, 2008

Chemistry
assuiming that the calorimeter contains 5.00 * 10^2 g of water and the intial temperature is 30.0 degreddc, what will the final temperature be?
October 19, 2008

chemistry
what is the 'big idea of energy'???!
September 26, 2008

chemistry
how do i draw a particle model to describe the reaction between sulphur and iron in detail?
September 26, 2008

Chemistry
How do I find the empirical formula of FeSO4? Thanks!
June 5, 2008

French
How do you say "we watched the sunset" in French? Is it "nous avons regardé le coucher du soleil?" Merci!
October 1, 2007

French
I need help with the adjective bien et bon. How do you know when to use what in a sentance. For Example: Would it be. Maire danse bonne. or Marie danse bien. How can I tell the difference. Bonne/bon is an adjective meaning "good." Bien is an adverb meaning "well...
June 20, 2007

French
How do you say "if you want to read this..." in French? Would it be "Si vous voulez lire ceci...?" Thank you for using the Jiskha Homework Help Forum. Yes, that is one way. To be more polite, you might say "if you wish..." = Si vous voudriez.....
June 7, 2007

the big idea of energy
don' fikin ask me! got nooooooooo idea AT ALLLLLLLLLLLLLLLLLLLLLLLLLLLLLL!
December 5, 2006

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