Sunday

February 14, 2016
Total # Posts: 2,650

**Chemistry AP**

I don't quite understand why you multiplied 10.501 (density of silver) by (1-x). And what was the point of the problem talking about "assume that the volume of silver present plus the volume of copper.."? Thanks for your help Steve
*July 11, 2013*

**Chemistry AP**

I'm using Zumdahl 7th Edition Chemistry Book and I'm having trouble with some practice problems in the first chapter. Here are a few: 87: Sterling silver is a solid solution of silver and copper. If a piece of a sterling silver necklace has a mass of 105.0 g and a ...
*July 11, 2013*

**Math**

If 1 more than a certain number is 3 less than a second number, the larger of these numbers minus the smaller is equal to?
*July 1, 2013*

**Math**

Oatmeal Recipe: Water 3/4 cup Salt: 1/4 teaspoon Oats: 1/3 cup If the least possible multiple of the recipe above is prepared so that a whole number of cups of both water and oats are used, how many teaspoons of salt would be required?
*July 1, 2013*

**Math Gr 11**

"A rock is dropped from the edge of a 180 m cliff. the function f(x) = -5t^2 - 5t + 180 gives the height of the rock, h(t), in meters t seconds after it was released. How long does it take for the rock to reach a ledge 80 m above the base of the cliff?" I have no ...
*June 20, 2013*

**Math**

an algorithm word problem
*June 3, 2013*

**geometry**

450 cm3
*May 23, 2013*

**first additional language **

how did youth day came?
*May 19, 2013*

**math**

what is the rule of the input output table input 2 output 11 input 3 output 15 input 5 output 18 input 8 output? what is the rule?
*May 15, 2013*

**C/Justice**

it could be B.
*May 9, 2013*

**C/Justice**

The inmate code is: A. the set of rules for inmate behavior established by prison officials. B. an informal set of rules of inmate behavior that is part of the prison culture. C. a secret language inmates use to communicate with each other in the presence of guards or other ...
*May 9, 2013*

**C/J**

The role of the defense attorney is to: A. decide the innocence of the accused. B. get his or her client off by whatever means. C. give the client every resource available to defend himself or herself within the limits of ethics and law. D. act as a legal technician to get his...
*May 8, 2013*

**life orientation **

5 ways in which the human or environmental problem impact on the community on Hiv&aids
*May 8, 2013*

**help please **

Although its meaning may vary from one culture to the next, __________ appears to be an almost universal taboo. A. murder B. rape C. theft D. incest D am i correct?
*May 4, 2013*

**Physics 1**

A steel wire in a piano has a length of 0.5000 m and a mass of 3.800 10-3 kg. To what tension must this wire be stretched in order that the fundamental vibration correspond to middle C (fC = 261.6 Hz on the chromatic musical scale)?
*May 3, 2013*

**Health**

10/10 100% Correct
*May 2, 2013*

**calculus**

Find the derivative y = e^(-5x) + cos^3 x F(x)= (x^2 -x+1)^3
*April 29, 2013*

**Chemistry **

A sample of argon gas at STP occupies 56.2 liters. Find the number of moles of argon and the mass in the sample
*April 27, 2013*

**Math**

How do you find the equation of a line with a slope of 2 and containing the points 1,5
*April 25, 2013*

**math**

An alcohol solution consists of 6 gallons of pure water and x gallons of alcohol, x > 0. Let f(x) be the ratio of the volume of alcohol to the total volume of liquid. [Note that f(x) is the concentration of the alcohol in the solution.] (a) Find a possible formula for f(x).
*April 23, 2013*

**landmark project**

thank you but can you help me think of 3 questions for palace of fine arts
*April 23, 2013*

**landmark project**

I am not impatient
*April 23, 2013*

**landmark project**

please
*April 23, 2013*

**landmark project**

i really need help
*April 23, 2013*

**landmark project**

did any workers die while building the palace of fine arts
*April 23, 2013*

**landmark project**

did any workers die while building the palace of fine
*April 23, 2013*

**math**

An alcohol solution consists of 6 gallons of pure water and x gallons of alcohol, x > 0. Let f(x) be the ratio of the volume of alcohol to the total volume of liquid. [Note that f(x) is the concentration of the alcohol in the solution.] (a) Find a possible formula for f(x).
*April 23, 2013*

**Math**

The invested in a bank savings accouint is coumpounded continousl, with an annual interest rate of 3%. If a deposit of $2000 is made, then determine the balance after 2 years
*April 22, 2013*

**physics**

Two speakers are wired to emit identical sounds in unison. The wavelength in air of the sounds is 6 m. Do the sounds interfere constructively or destructively at a point 10 m from both speakers? 1. Destructively 2. Neither 3. Constructively
*April 21, 2013*

**General Chemistry**

"How would you prepare 150. mL of 0.1M sodium hydroxide given a stock solution of 3.0M NaOH?" I made calculations and figured the process would be to dilute 5 mL of the 3.0M NaOH to 150. mL. Is this correct? For the ideal 150. mL of 0.1M NaOH, I calculated there to ...
*April 21, 2013*

**math**

Take an 17 by 11-inch piece of paper and cut out four equal squares from the corners. Fold up the sides to create an open box. Find the dimensions of the box that has maximum volume. (Enter your answers as a comma-separated list. Round your answer to three decimal places.)
*April 21, 2013*

**Calculus**

A University of Rochester student decided to depart from Earth after his graduation to find work on Mars. Before building a shuttle, he conducted careful calculations. A model for the velocity of the shuttle, from liftoff at t = 0 s until the solid rocket boosters were ...
*April 21, 2013*

**Physics**

A convex lens of focal length 2.5 cm is placed 4 cm from a small object of height 4 cm. Use a ruler and construct the image. Is the image real or virtual, upright or inverted? What is the image distance? What is the height of the image? What is the magnification?
*April 21, 2013*

**landmarks**

none of those tell me who named palace of fine arts
*April 20, 2013*

**landmarks**

ther are so many websites , i do not know which website do you want me to read about
*April 20, 2013*

**landmarks**

i dont get it
*April 20, 2013*

**landmarks**

how did Palace Of Fine Arts got its name
*April 20, 2013*

**Find the avg rate**

Find the average rate of change f(x)=x^3-3x+9 (a) from -4 to -3 (b) from -2 to 5 (c) from 5 to 9
*April 19, 2013*

**Algebra**

For the given equation, list the intercepts and test for symmetry. 2+y-121=0 Show tests algebraically
*April 19, 2013*

**math**

he should be puling with 66 pounds of force
*April 18, 2013*

**Please Help! Rate of change...**

Taxes: Along with incomes, peoples charitable contributions have steadily increased over the past few years. The table shows the average deduction for charitable contributions reported on individual income tax returns for the period 2007 to 2012. Find the average rate of ...
*April 18, 2013*

**Math**

Mack needs to buy fencing to surround his circular garden. If his garden is 30 feet across and fencing cost $4.50 per foot, how much will it cost to fence in Mark's garden? If the radius if of a circle is 4 feet, what is its circumference ? Ben ran 10 times around a ...
*April 17, 2013*

**Find the rate of change**

Taxes: Along with incomes, peoples charitable contributions have steadily increased over the past few years. The table shows the average deduction for charitable contributions reported on individual income tax returns for the period 2007 to 2012. Find the average rate of ...
*April 17, 2013*

**Math**

A meteoroid changed velocity from 1.0 km/s to 1.8 km/s in 0.03 seconds. What is the acceleration of the meteoroid?
*April 16, 2013*

**Science**

In 0.5 seconds, a projectile goes from 0 to 300m/s. what is the acceleration of the projectile?
*April 16, 2013*

**Algebra 1**

Solve for y=x-5
*April 15, 2013*

**math**

Let 2^a = 5 and 2^b = 7. Using exponent rules, solve the equation in terms of a and b. 0.4^x = 343
*April 14, 2013*

**Math**

Thanks!
*April 14, 2013*

**Math**

What is 8/9 as a percent, as a decimal, and a decimal rounded to two places?
*April 14, 2013*

**Physics**

no its still just wrong
*April 14, 2013*

**Physics**

That is wrong
*April 14, 2013*

**Physics**

A rotating uniform-density disk of radius 0.6 m is mounted in the vertical plane. The axle is held up by supports that are not shown, and the disk is free to rotate on the nearly frictionless axle. The disk has mass 5.8 kg. A lump of clay with mass 0.5 kg falls and sticks to ...
*April 14, 2013*

**Physics**

11-098-satellite_and_junk.jpg A spherical satellite of radius 4.6 m and mass M = 195 kg is originally moving with velocity vsatellite,i = < 3000, 0, 0 > m/s, and is originally rotating with an angular speed ?1 = 2 radians/second, in the direction shown in the diagram. A ...
*April 14, 2013*

**Physics**

A device consists of eight balls each of mass 0.4 kg attached to the ends of low-mass spokes of length 1.8 m, so the radius of rotation of the balls is 0.9 m. The device is mounted in the vertical plane. The axle is held up by supports that are not shown, and the wheel is ...
*April 14, 2013*

**CHEM QUICK HELP**

Which of the following are correct statements? (Could be as many as 4) 1. Standard pressure is 101.3 atmospheres 2. One mole of gas contains 22.4 representative particles 3. One mole of gas always occupies 22.4 liters regardless of other conditions 4. Solids can always be ...
*April 11, 2013*

**math**

Thank you!
*April 10, 2013*

**math**

Dad baked a batch of cookies. My brother ate half my mom ate a fourth of the batch. Dad ate 3 and I ate the last two. How many cookie did dad bake? PLEASE help me figure this problem out?
*April 10, 2013*

**math**

A population of animals oscillates between a low of 1098 on January 1 (t = 0) and a high of 2344 on July 1 (t = 6). (a) Find a formula for the population, P, in terms of the time, t, in months.
*April 9, 2013*

**Physics**

A car has a unibody-type frame and is supported by four suspension springs, each with a force constant of 36100 N/m. The combined mass of the car’s frame and everything inside it (the engine, the seats, the passengers, etc.) is 1270 kg. Because of worn-out shockabsorbers...
*April 7, 2013*

**Physics**

A particle hangs from a spring and oscillates with a period of 0.2 s.If the mass-spring system remained at rest, by how much would the mass stretch it from its normal equilibrium position? The acceleration of gravity is 9.8 m/s^2
*April 7, 2013*

**Physics**

A mass of 0.22 kg is attached to a spring and is set into vibration with a period of 0.10 s. What is the spring constant of the spring? Answer in units of N/m
*April 7, 2013*

**General Chemistry**

What volume of 1.0 M HCl would react completely with 0.20 grams of NaC2H3O2*3H2O? It sounds like an equation I would set up as this and would use mole ratios to calculate the answer: HCl + NaC2H3O2*3H2O --> But I am confused as to what I would put as the products, let alone...
*April 7, 2013*

**Math**

A C D A B
*April 5, 2013*

**Chmeistry**

Estimate the uncertainty in the speed of an oxygen molecule if its position is known to be +/- 3 nm. The mass of an oxygen molecule is 5.31 x 10^26 kg.
*April 4, 2013*

**General Chemistry**

Balance the following redox reaction in acidic and basic solutions: Fe(OH)2(s) + O2(g) --> Fe(OH)3(s) These are the steps my instructor gave us to balance redox reactions: 1. Divide into 1/2 rxns (reduction & oxidation) 2. Balance atoms other than H & O 3. Balance O with ...
*April 3, 2013*

**Physics 1**

A coin rests 12.0 cm from the center of a turntable. The coefficient of static friction between the coin and turntable surface is 0.350. The turntable starts from rest at t = 0 and rotates with a constant angular acceleration of 0.749 rad/s2. After what period of time will the...
*April 1, 2013*

**language arts**

it is a spring break pratice book
*March 29, 2013*

**language arts**

but i need help i am only in third grade
*March 29, 2013*

**language arts**

true or false. 1. it is easy to walk across something impassable. 2. ice sheets floating on water are called floes. 3. land that is barren has many plants and animals. 4. a crevasse is a deep crack.
*March 29, 2013*

**english**

Special education services for young children are with disabilities a. cannot be enforced through laws b. depend on parent efforts c. do not involve the head Start program d. are rooted in federal legislation My answer is d.
*March 28, 2013*

**math**

You are at the music store to buy some CDs. You have $45 to spend and the store sells CDs for 12.99 each. Write an inequality that represents the number, n, of CDs that you can buy without spending more money than you have. help greatly appreciated thk
*March 27, 2013*

**geography**

The OB river flows through which region a. Central Asia b. Siberia c. Moldova d. Ukraine a or b not sure I think B is more correct am i right?
*March 26, 2013*

**Science **

Calculate the quantity of energy required to change 3.00 mol of liquid water to steam at 100°C. The molar heat of vaporization of water is 40.6 kj/mol
*March 25, 2013*

**Biology { PLEASE HELP :D }**

From an ATP production viewpoint, use fact B to make a statement regarding the efficiency of fats vs. carbs. Fact b - Carbs bind and store water. The metabolism of water yields no ATP. Fat has no water bound to it.
*March 25, 2013*

**organic chemistry**

Did a grignard experiment where we were supposed to form triphenylmethanol but something went wrong. When we heated up the mixture with the petroleum ether, it didn't solidify, it turned dark and oily. What went wrong?
*March 25, 2013*

**organic chem**

I prepared triphenylmethanol by a grignard reaction. At the end you add petroleum ether to the mixture and heat it up. It stayed a liquid and got dark and oily but never solidified. What went wrong?
*March 25, 2013*

**Stats**

Is noise present in the differenced series (taking non-stationary data and making it stationary thru first difference of a time series)?
*March 23, 2013*

**language arts**

thank you
*March 23, 2013*

**language arts**

what is the past tense of go
*March 23, 2013*

**language arts**

i get it now
*March 23, 2013*

**language arts**

i do not get it
*March 23, 2013*

**language arts**

what is the exact verb of swam
*March 23, 2013*

**Curriculum dev**

Behavior objectives should be written about a behavior that a) is exhibited by most chlldren. B) can actually be seen. C) exhibits all five selves. D) can be evaluated using standardized test. I think a) is exhibited by most children. CAn someone give me some feedback
*March 20, 2013*

**Math**

Find the difference between the perimeter of a square of area 1 centimeter square and the circumference of a circle of the same area.
*March 20, 2013*

**Math**

A lorry travels at 50km/h. Given that the diameter of its wheel is 88cm, find how many revolutions per minute the wheel is turning. Given your answer to the nearest whole number.
*March 20, 2013*

**Math **

Find the speed of a point on the rim of a 24cm diameter fly wheel which is turning at 2800 revolutions per minute. Give your answer in meters per second.
*March 20, 2013*

**Math**

If the minute hand of a big clock is 1.12m long, find the rate at which its tip is moving in centimeters per minute.
*March 20, 2013*

**Math**

As many 8cm diameter discs as possible are cut from a sheet of rectangular cardboard measuring 170cm by 90cm. Find the area of the sheet that is left.
*March 20, 2013*

**Algebra**

You are right on!
*March 19, 2013*

**Physics**

That is why I'm asking. If u don't know, then don't answer my question
*March 19, 2013*

**Physics**

How can we find the resultant force if the mass and SPEED are given?? Give me the formula please!!
*March 19, 2013*

**Statistics**

The eggs of a species of bird have an average diameter of 23 mm and an SD of 0.45 mm. The weights of the chicks that hatch from these eggs have an average of 6 grams and an SD of 0.5 grams. The correlation between the two variables is 0.75 and the scatter diagram is roughly ...
*March 15, 2013*

**Statistics**

A quiz consists of 10 multiple choice questions. Each question is marked either “right” or “wrong.” Each right answer gets 5 points, and 1 point is taken off for each wrong answer. The correlation between the number of right answers and the number of wrong ...
*March 15, 2013*

**Physics 1**

An astronaut in her space suit has a total mass of m1 = 76.9 kg, including suit and oxygen tank. Her tether line loses its attachment to her spacecraft while she's on a spacewalk. Initially at rest with respect to her spacecraft, she throws her oxygen tank of mass m2 = 12....
*March 14, 2013*

**Math**

The cost C in dollars of producing n yearbooks is represented by the equation C=1000+5n How much would it cost to produce 75n yearbooks?
*March 13, 2013*

**biology**

what is deep time?
*March 11, 2013*

**Bioprocessing**

A continuously operated 1000 liter CSTR is used for production of biomass from glucose provided by the feed (feed rate of 100l/h and glucose concentration of 10 g/l). The bacteria show Monod type growth with a maximal specific growth rate of 0.4/h and an affinity towards ...
*March 11, 2013*

**algebra **

Scientists can determine the age of ancient objects by a method called radio carbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope 14C of carbon with a half-life of about 5710 years. Vegetation absorbs carbon dioxide ...
*March 7, 2013*

**Chemistry**

Why is why is CH4+2O2 --> CO2+2H2O very slow at room temperature?
*March 6, 2013*