Wednesday
October 1, 2014

Posts by Rachel


Total # Posts: 1,191

Geometry
how to you solve: the radius of circle Z is 13.5 units long. Find the length of each arc for the given angle measure. if the angle measure is 120 degrees?
April 19, 2011

Calculus
Hey, we covered limits at the beginning of the year, but I cannot remember how to do them at all. >>>what is the limit, as x approaches 2, of ((1/x )-(1/2))/(x-2)? Please go step by step!
April 18, 2011

math
a cross section of a hollow circular pipe shows that its inner diameter is 2 1/10inches and that the pipe is 3/5inch thick. what is the outside diameter
April 18, 2011

economics
Jerry will receive the following payments: 946 in year 3, 929 in year 5 and 958 in year 9. What is the purchasing power of the present value of these payments if the market interest rate is 17% per year and the inflation rate is 6% per year?
April 17, 2011

economics
Tom plans to gamble each year for the next 20 years, starting at at the end of year 1. If he loses 4.47 dollars in odd years (i.e., years 1, 3, 5, etc) and wins 7.46 dollars in even years (i.e., years 2,4, 6 etc), what will be Tom's (internal) rate of return per year from ...
April 17, 2011

economics
Consider a project with a positive rate of return. Suppose the discount factor solutions to the equation which determines the internal rate of return (ROR) of the project are given by 0.8502, 2.0207, -0.1767. What is the project's ROR?
April 17, 2011

Chem (repost)
Hydrogen and carbon dioxide react at a high temperature to give water and carbon monoxide. H2(g) + CO2(g) --> H2O(g) + CO(g) (b) Suppose 0.052 mol each of H2 and CO2 are placed in a 1.5 L container. When equilibrium is achieved at 986°C, what amounts of CO(g) and H2O(g...
April 17, 2011

Chemistry(check my work)?
An equilibrium mixture of the following reaction was found to have [COF2] = 0.255 M and [CF4] = 0.118 M at 1000°C. What is the concentration of CO2? 2 COF2(g) ---> CO2(g) + CF4(g) Keq = 2.00 at 1000°C I know I need to put the numbers in the equation so this is what ...
April 17, 2011

How many sig figs?
Thanks:)
April 17, 2011

How many sig figs?
An equilibrium mixture of the following reaction was found to have [H2] = 0.020 M and [I2] = 0.020 M at 340°C. What is the concentration of HI? H2(g) + I2(g)--> 2 HI(g) Keq = 69 at 340°C I got .166 but it said check number of sig figs so im guessing its 2 sig figs ...
April 17, 2011

chem
Sorry I am soo confussed right now O.O. is there anyway u can explain this in simplier form?
April 16, 2011

chem
ok so I did (x)(x)/(.03466)(.03466)= 1.6. I solved for x and got .0438. Do I have to do anything with this number to get the correct answer? Can you check my work? Thanks:)
April 16, 2011

chem
thanks Would you get the same answer for both parts of b?
April 16, 2011

chem
Hydrogen and carbon dioxide react at a high temperature to give water and carbon monoxide. H2(g) + CO2(g) --> H2O(g) + CO(g) (a) Laboratory measurements at 986°C show that there are 0.11 mol each of CO and H2O vapor and 0.087 mol each of H2 and CO2 at equilibrium in a 1...
April 16, 2011

Chemistry
Nevermind I got it:)
April 16, 2011

Chemistry
An equilibrium mixture of SO2, O2, and SO3 at 1000 K contains the gases at the following concentrations: [SO2] = 3.77 10-3 mol/L, [O2] = 4.30 10-3 mol/L, and [SO3] = 4.13 10-3 mol/L. Calculate the equilibrium constant, K, for the following reaction. 2 SO2(g) + O2(g) ---> 2 ...
April 16, 2011

science
I am really confused on this too. I'm pretty sure you come from Connections Academy. What I did was gon on google and search saturated and unsaturated. It should help a bit?
April 11, 2011

Chemistry (repost)
Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5?? chem - DrBob222, Sunday, April 10, 2011 at 1:28am...
April 10, 2011

chem
I tried those and it was wrong
April 9, 2011

chem
Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5??
April 9, 2011

physics
Two very long, straight, parallel wires carry currents that are directed perpendicular. Wire 1 carries a current I1 into the page (in the -z direction) and passes through the x axis at x = +a. Wire 2 passes through the x axis at x = -2a and carries an unknown current I2. The ...
April 9, 2011

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...
April 9, 2011

physics
oh alright sir thank you!
April 9, 2011

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the ...
April 9, 2011

Physics
Thank you for your help. I am still unsure on the formulas I am meant to be using and when I am meant to be converting from mmHg to Pa.
April 8, 2011

Physics
I have been given this question and with very little knowledge of physics and a book and flex studies that I am not finding very explanitory. I am not sure I am on the correct path as the vlaues I have seem very large. I would appreciate any help/assistance anyone could give. ...
April 8, 2011

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...
April 8, 2011

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...
April 8, 2011

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...
April 8, 2011

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, ...
April 8, 2011

Chemistry
Find the Ph: of 7.01 x 10-5 M Ba(OH)2 thanks:)
April 7, 2011

calculus
what is the integral of [e^(11x)]/[e^(11x)+8]
April 7, 2011

Chemistry!
a microwave oven uses electromagnetic radiation with a wavelength of 3.00x10^6 nm. calculate energy (in joules) of 1.65 moles of photons of this radiation.
April 6, 2011

physics
sir i read through the site so when i use force 0 how should i solve this question? thank you
April 5, 2011

physics
An accelerating voltage of 2.46 * 10^3 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 34.0 cm away. What is the magnitude of the deflection on the screen caused by the Earth...
April 5, 2011

physics
so sir in this formula. I = 120mA B = 0.0840 T n = 8.47 * 10^28 q = 1.6 * 10 ^ -19 t = 2.00 mm but how do i calculate d?
April 5, 2011

physics
sir should i use this formula V = IB/nqt thanks you
April 5, 2011

physics
oh ok sir thank you. The thickness of the probe in the direction of B is 2.00 mm. Find the density of the charge carriers, each of which has charge of magnitude e). thank you again sir
April 5, 2011

physics
A Hall-effect probe operates with a 120 -mA current. When the probe is placed in a uniform magnetic field of magnitude 0.0840 T, it produces a Hall voltage of 0.660 µV. When it is used to measure an unknown magnetic field, the Hall voltage is 0.360 µV. What is the ...
April 5, 2011

geometry
what is the area of a circle with a circumference of 22 pi in.? expressed in pi in. squared? and what are the steps to arrive at the solution?
April 5, 2011

Math
10^-8
April 4, 2011

Chemistry.
The complete combusion of 0.5763 grams of glucose in a bomb calorimeter (Cbomb = 6.20 kJ/degrees C) raises the temperature of the calorimeter by 1.45 degrees C. what is the food value of glucose in calories per gram? (Hint: remember 1 Cal = 4.184 kJ) i do not know how to find ...
March 29, 2011

Geometry
1. Graph the quadrilateral with vertices C(-9,4), D(-4,8), E(2,6), and F(-3,2). What specific shape is it? 2. Include the work with explanations of how you solved this. 3. List at least 2 other ways you could have proved this. You do not have to prove these additional ways, ...
March 29, 2011

chemistry, please help!!
The combusion of glucose produces carbon dioxide and water vapor according to the chemical equation below: C6H12O6 (s) + 6O2 (g) ---> 6CO2 (g) + 6H2O (g) DELTA H = -2540 kj Calculate the energ involved in making 75.0 g of glucose from carbon dioxide and liquid water (...
March 28, 2011

economics
What is the face value of a municipal bond that has a bond (or coupon) interest rate of 6% per year and makes interest payments of 578 dollars every 1 months?
March 27, 2011

physics
A proton moves at 3.60 *10^5 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 8.20* 10^3 N/C. Find the time interval required for the proton to travel 4.00 cm horizontally. thanks
March 27, 2011

physics
A uniform electric field of magnitude 320 V/m is directed in the negative y direction. The coordinates of point A are (-0.300, -0.450) m, and those of point B are (0.650, 0.300) m. Calculate the electric potential difference VB − VA. thanks
March 27, 2011

physics
A copper wire has a circular cross section with a radius of 3.75 mm. If the wire carries a current of 4.00 A, find the drift speed of the electrons in the wire. (Assume the density of charge carriers (electrons) in a copper wire is n = 8.46 *10^28 electrons/m^3.) thanks
March 27, 2011

physics
An electron moving parallel to the x axis has an initial speed of 4.82 *10^6 m/s at the origin. Its speed is reduced to 1.46 * 10^5 m/s at the point x = 2.00 cm. Calculate the electric potential difference between the origin and that point.
March 27, 2011

physics
A proton is projected in the positive x direction into a region of uniform electric field E = (-6.80 * 10^5 N/C at t = 0. The proton travels 6.80 cm as it comes to rest. (a) Determine the acceleration of the proton. thanks
March 27, 2011

physics
A proton moves at 3.60 *10^5 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 8.20* 10^3 N/C. Find the time interval required for the proton to travel 4.00 cm horizontally. thanks
March 27, 2011

physics
A uniform electric field of magnitude 320 V/m is directed in the negative y direction. The coordinates of point A are (-0.300, -0.450) m, and those of point B are (0.650, 0.300) m. Calculate the electric potential difference VB − VA. thanks
March 27, 2011

physics
A copper wire has a circular cross section with a radius of 3.75 mm. If the wire carries a current of 4.00 A, find the drift speed of the electrons in the wire. (Assume the density of charge carriers (electrons) in a copper wire is n = 8.46 *10^28 electrons/m^3.) thanks
March 27, 2011

physics
An electron moving parallel to the x axis has an initial speed of 4.82 *10^6 m/s at the origin. Its speed is reduced to 1.46 * 10^5 m/s at the point x = 2.00 cm. Calculate the electric potential difference between the origin and that point.
March 27, 2011

physics
A proton is projected in the positive x direction into a region of uniform electric field E = (-6.80 * 10^5 N/C at t = 0. The proton travels 6.80 cm as it comes to rest. (a) Determine the acceleration of the proton. thanks
March 27, 2011

physics
(a) Calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 8.0 g. Silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) Imagine adding electrons to the pin until the negative charge has the very large value 2.00 mC...
March 26, 2011

math
a bag full of gum drops. 2/3 of which are blue. the red drops are 3/8 of the number of blue. There are 3 green drops. How many drops in the bag?
March 25, 2011

Science
The water molecules now in your body were once part of a molecular cloud. Only about onemillionth of the mass of a molecular cloud is in the form of water molecules, and the mass density of such a cloud is roughly 4.0×10−21 {\rm g}/{\rm cm}^{3} Estimate the volume ...
March 24, 2011

Music
Can you please check my answers. 1. A lyrical movement or piece for solo voice with instrumental accompaniment is called a/an A. ostinato. B. aria. C. operetta. D. chorus. 2. What is the difference between an oratorio and an opera? A. An opera is staged and an oratorio isn'...
March 23, 2011

english
what does juliet ask romeo to do and what does she promise to do
March 23, 2011

Grade 12 Chemistry
Determine the concentration of a calcium chloride solution if 1.75 L of the solution contains 0.125 mol of calcium chloride.
March 22, 2011

Math
A coin is tossed 13 times. How many different outcomes have at least 2 heads ?
March 22, 2011

AP Chem
A student performs an experiment to determine the enthalpy of neutralization of hydrochloric acid and sodium hydroxide. The student combines 25 mL of equimolar solutions of acid and base, both having an initial temperature of 22.5 C, in an open polystyrene calorimeter. Each ...
March 22, 2011

history
give two reasons that chinas policy of limiting trade with foreigners ended after the 1700's
March 21, 2011

Chemistry
What mass of silver chloride can be prepared by the reaction of 160.0 mL of 0.10 M silver nitrate with 120.0 mL of 0.19 M calcium chloride?
March 15, 2011

US History
I dont have an answer, thats the thing.
March 14, 2011

US History
What can you infer about Truman's successful tactic of attacking the "do-nothing congress"?
March 14, 2011

Chemisty!
a flask with a volume of 267.5 mL contains a few milliliters of a volatile hydrocarbon. after vaporizing the gas at 100 degrees C, the flask is weighed and found to contain 0.728 grams of hydrocarbon vapor at 755 mmHg. a seperate combustion analysis experiment revealed that ...
March 14, 2011

chemistry
a flask with a volume of 267.5 mL contains a few milliliters of a volatile hydrocarbon. after vaporizing the gas at 100 degrees C, the flask is weighed and found to contain 0.728 grams of hydrocarbon vapor at 755 mmHg. a seperate combustion analysis experiment revealed that ...
March 14, 2011

chemistry
A 150.0 mL flask contains 0.391 grams of a volatile oxide of sulfur. The pressure in the flask is 750 mmHg and the temperature is 22C. Is the gas SO2 or SO3?
March 14, 2011

economics
Eric borrowed 515 dollars today and has agreed to pay back in equal monthly installments over 6 years. The bank charges Eric 4.94% per year, compounded monthly. What is the amount that Eric will owe the bank at the end of month 20 (that is, after the 20-th installment has ...
March 13, 2011

English 9-Thanks-I responded under my sister's page-Sorry-
My sister also posted something today and when I went back to respond to you, I accidentally responded under her last response page-Sorry for the confusion Thanks again for all your help
March 13, 2011

English 9-WritteacherPlease recheck answer and provide some d
Another way is to put in "Sons" by John Updike and then the nexuslearning site is listed in dogpile
March 13, 2011

English 9-WritteacherPlease recheck answer and provide some d
I just put as much of thewebsite above as I could-it wouldn't allow me to actually put the entire address in
March 13, 2011

English 9-Please recheck answer and provide some d
Here is the site-I found it again-it would the usual and then-nexuslearning and then Elements of Lit with underscores between them and then hyphen and Course5 Thank you for checking this-I really appreciate it
March 13, 2011

English 9-Writteacher could youPlease recheck answer and provide some d
I put the website in the last response-I found it online for you-Thanks for any additional help you could provide
March 13, 2011

English 9-Please recheck answer and provide some d
It's a story about a father recalling details of present day son and then reverts back to himself,his dad and his dad's dad and then back to present son-so that's why I eliminated "c" The story is at nexuslearningwebsite if you're looking for it ...
March 13, 2011

English 9-Please recheck answer and provide some d
I have a question about the short story "Son" by John Updike. I have research this and read it but find it very confusing-I have two answers totally eliminated and would just like some input-Thank you so much Is "Son told in a.order from the contemporary father ...
March 13, 2011

Spanish 7th grade
The actual wording is "If something is dulce, one would probably want to drink lemonade or something sour" and I have to answer with a yes or no-That was the exact homework question-I thought it was odd so that's why I posted it
March 13, 2011

physics
Suppose a cylindrical habitat in space 7.70 km in diameter and 25.0 km long has been proposed. Such a habitat would have cities, land, and lakes on the inside surface and air and clouds in the center. They would all be held in place by rotation of the cylinder about its long ...
March 11, 2011

physics
Two hypothetical planets of masses m1 and m2 and radii r1 and r2, respectively, are nearly at rest when they are an infinite distance apart. Because of their gravitational attraction, they head toward each other on a collision course. Note: Both the energy and momentum of the ...
March 11, 2011

physics
ok sir is the formula -(1/2)GmM/R
March 11, 2011

physics
A 981-kg satellite orbits the Earth at a constant altitude of 103-km. How much energy must be added to the system to move the satellite into a circular orbit with altitude 199 km? I need answer in MJ please tell me what formula
March 11, 2011

physics
Thank you very much sir!
March 11, 2011

physics
A system consists of three particles, each of mass 2.10 g, located at the corners of an equilateral triangle with sides of 22.0 cm. Calculate the potential energy of the system. Please help me what formula to use please
March 11, 2011

physics
What is the minimum speed, relative to the Sun, necessary for a spacecraft to escape the solar system if it starts at the Earth's orbit? Please tell me what formula
March 11, 2011

PHYSICS
At the Earth's surface, a projectile is launched straight up at a speed of 8.4 km/s. To what height will it rise? Ignore air resistance and the rotation of the Earth.
March 11, 2011

PHYSICS
How much work is done by the Moon's gravitational field as a 1005 kg meteor comes in from outer space and impacts on the Moon's surface? PLEASEEEEEEEEEE
March 10, 2011

chemistry
What mass of NaCl can be dissolved in 250 g of water at 20 degrees C?
March 10, 2011

Child Care
1. The interaction between a child's biological makeup and the environmental influences that affect his or her development and behavior is called the a) balanced systems approach b) ecological systems theory c) body in the classroom analysis d) me/them dynamic 2. Alcohol, ...
March 9, 2011

Spanish-8th Grade-Please check
I have a question about the owrd cubiertos in Spanish. Does ths word include la servillete el cuchillo el vaso la cuchara el tendor OR is it just like the plate and spoon, fork, knife and NOT the vaso or servillete(napkin)? The word and transaltion is confusing me Thank you
March 8, 2011

Genetics
Question 11 (1 point) Save As the degree of relatedness within a population increases, the level of inbreeding in that population also increases. As relatedness and inbreeding go up, individuals become more similar genetically and therefore genetic variability goes down. How ...
March 6, 2011

Stats
if a researcher were studying the effects of a teaching method on patient learning outcomes, how must he or she word the research question (different from hypothesis) to use the t-test for statistical differences? What type of data must he or she collect (interval, ratio, ...
March 5, 2011

Science
To disinegrate due to mixing with a fluid
March 4, 2011

science
two equally charged spheres, X and Y, repel each other with a force of 8.0 x 10^-6 N when placed a certain distance apart. Another identical, but uncharged, sphere is touched to sphere Y and then moved next to sphere X. Calculate the electric force acting on sphere Y.
March 4, 2011

Physics
A parallel-plate capacitor is made from two plates 12.0cm on each side and 4.50mm apart. Half of the space between these plates contains only air, but the other half is filled with Plexiglas of dielectric constant 3.40. An 18.0 V battery is connected across the plates. What is...
March 3, 2011

U.S.History- 8th grade
Could someone help me with this question? Which of the following groups of workers lived in poverty? nurses unskilled workes technicians immigrants I'm torn between unskilled workers and immigrants
March 3, 2011

Medical Office Asst
On the ADA for Keith Konklin, the number 333-2589 should be placed in block A( #7 B) # 18 C0 # 19 D) #31
March 1, 2011

English
In the poem "Home Burial", who do you think was in the right, the husband Amy? I believe Amy was in the right because, he shouldnn't have walked in the house talking about the fence, after leaving his son's grave. A fence would have been the last thing on my ...
February 28, 2011

Calculus
I'm a bit confused about the average equations with integration. I need to solve this problem, and I think I'm supposed to use substitution, but I can't get it to work. The problem looks like this: z(t)=4tsin(t^2), [0,π^1/2] Any input?
February 27, 2011

Pages: <<Prev | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | Next>>

Search
Members