# Posts by Kelsey

Total # Posts: 596

**Physics**

A bicyclist is coasting straight down a hill at a constant speed. The mass of the rider and bicycle is 55.0 kg, and the hill is inclined at 16.0° with respect to the horizontal. Air resistance opposes the motion of the cyclist. Later, the bicyclist climbs the same hill at ...

**Probability**

0.062

**Spelling Skills**

Use the spelling words in the boxes below to complete the story. Then use proofreading marks to correct mistakes in the use of capital letters and periods.

**calculus**

A trough is 12 feet long and 3 feet across at the top. It ends are isosceles triangles with a height of 3 feet. If water is being pumped into the trough at 2.5 cubic feet per minute, how fast is the water level rising when the water is 1 foot deep?

**Chemistry**

How many grams of formaldehyde, H2CO, are in 500 ml of a 40% solution of formaldehyde in water? (Assume for this problem that the density of the formalin solution is 0.98 g/ml)

**chemistry**

How many grams of sodium were isolated from the decomposition of 0.0292 moles of Na2O, if the reaction occurred with a 44.9% percent yeild? 2 Na2O(s) --> 4 Na(s) + O2(g)

**chemistry**

How many molecules of NH3 could be generated from 64 molecules of N2 and 210 molecules of H2? How many molecules of N2 and H2 would be left over after the reaction?

**chemistry**

How many molecules of NH3 could be generated from 64 molecules of N2 and 210 molecules of H2? How many molecules of N2 and H2 would be left over after the reaction?

**Physics**

An object is in free fall. At one instant, it is traveling at 41 m/s. Exactly 3.2 s later, what is its speed? The acceleration of gravity is 9.8 m/s2 . Answer in units of m/s

**Science**

Hi, I am needing help with the following question. How long would it take to produce 150 kW with 780 J of energy? (make sure you have the corerct units)

**programming**

How do i read in a vector of integers with a space inbetween (i.e. 0 1 2 3) and make it an integer array? in java

**Physics**

A small ferryboat is 4.00 m wide and 6.00 m long. When a loaded truck pulls onto it, the boat sinks an additional 4.80 cm into the water. What is the weight of the truck?

**Spanish-8th gradePlease check**

1.¿Tienes que hacer mucha tarea hoy? Sí, tengo que hacer mucha tarea hoy. 2.¿Cómo vas al parque? Voy a pie. 3.¿Dónde está la cocina en tu casa? En mi casa, la cocina está abajo. 4.¿Prefieres lavar la ropa o quitar ...

**Physics**

Kathy is changing the tire of her car on a steep hill 20 m high. She trips and drops the 10 kg spare tire which rolls down the hill. What is the speed of the tire at the top of the next hill if the height of the hill is 5 m high?

**Physics**

A player kicks a footbal with a velocity of 27 m/s at an angle of 31° with the ground. How high does the ball travel?

**physics**

but do not forget the answer is negative

**Chemistry**

When a sodium atom absorbs light at 330.2 nm, the 3s electron is promoted to the 4p level. How much energy would be required for ionization once the electron is in the 4p level?

**Chemistry**

When a sodium atom absorbs light at 330.2 nm, the 3s electron is promoted to the 4p level. How much energy would be required for ionization once the electron is in the 4p level?

**chemistry**

Thanks, How many atoms are in a body-centered cubic unit cell??? a- one b- two c- four d- six e- eight

**Chem**

How many grams of O2 are required to burn13.0g of acetylene? The answer I got is 40gO2 is this right.

**chem.**

How many grams of CO2 and grams of H2O are produced when 13.0g C2H2?

**chemistry**

How many grams of O2 are required to burn 13.0g of acetylene?

**US History**

How did the US become involved in the politics of Southeast Asia?

**History**

What did Kennedy hope to accomplish with the New Frontier?

**Personal Finance**

Mike Welch purchased 5,000 shares of Grass Roots stock for $82 per share and paid a commission of 1% on the purchase price. The current value of the stock is $96 per share. Mike received no dividends last year.

**physics**

1. A sound is made by a speaker, which then radiates in all directions. The sound wave is described by A(r) sin(2r - 600t) where the distances are in meters, and the time in seconds. The A(r) just indicates that the amplitude has some distance dependence--it decreases smoothly...

**science**

A 250 kg object is acceelerating at 2.8 m/s2. What force was required to achieve this?

**Algebra 2**

how do i find out what the amplitude, period, h, k and midline of problems 1) y= sin (x-5)=7 2) y=3 cos (x- pie) -1 3) y= Sin3x+4 4) y= 1/2 cos 2x-2

**Physics**

A 3 Kg lead ball is dropped into a 3 L insulated pail of water initially at 20.0 degrees C. If the final temperature of the water-lead combination is 25 degress C, what was the initial temperature of the lead ball?

**Chemistry**

A cubic piece of metal measures 7.50 cm on each edge. If the metal is nickel, whose density is 8.90g/cm^3, what is the mass of the cube?

**Physics**

A class of 11 students taking an exam has a power output per student of 124 W. Assume that the initial temperature of the room is 18.7°C and that its dimensions are 6.00 m by 14.5 m by 3.40 m. What is the temperature (in °C, do not enter units) of the room at the end ...

**VHS**

a triangle has sides with lengths of 11 meters, 9 meters, and 7 meters. what type of triangle is it?

**Controls**

If you have a tank of water at sea level and the temperature of the water in the tank is 110 degrees F, what is the height of the water if the pressure at the bottom of the tank is 95 inches of mercury(absolute)

**Chemistry**

The reaction of fluorine with ammonia produces dinitrogen tetrafluoride and hydrogen fluoride. 5 F2(g) + 2 NH3(g) N2F4(g) + 6 HF(g) (a) If you have 73.7 g NH3, how many grams of F2 are required for complete reaction? b) How many grams of NH3, are required to produce 5.25 g HF...

**Social Studies**

i donno

**Math**

To win one million dollars, you must draw two cards whose sum is nine, from a stack of cards numbered through 10. After the first draw you replace the card and shuffle the stack again for the the second draw. What is the chance that your two cards will have a sum of nine.?

**physics**

The blades of a fan running at low speed turn at 200 rpm. When the fan is switched to high speed, the rotation rate increases uniformly to 340 rpm in 5.92 s. How many revolutions do the blades go through while the fan is accelerating?

**Physics**

The blades of a fan running at low speed turn at 200 rpm. When the fan is switched to high speed, the rotation rate increases uniformly to 340 rpm in 5.92 s. (a) What is the magnitude of the angular acceleration of the blades? (b) How many revolutions do the blades go through ...

**Physics**

A 15500 N automobile travels at a speed of 41 km/h northward along a street, and a 7000 N sports car travels at a speed of 65 km/h eastward along an intersecting street. a)If neither driver brakes and the cars collide at the intersection and lock bumpers, what will the ...

**college math**

Express (cos^2t/tan^2t) as an expression that involves only the sine function.

**Science-Chemistry**

Calculate the number of grams of carbon dioxide that can be absorbed by a complete reaction with a solution that contains 5.00 grams of sodium hydroxide

**Math**

thank you very much damon!

**Math**

If a shopkeeper sold 15 boxes of pencils on Mon and Tues. He sold 3 more boxes on Mon then on Tues. There were 12 pencils in each box. How many pencils did he sell on Monday.

**math**

How do i do mixed numbers to improper fractions.

**Physics**

A 15.0 g rubber bullet hits a wall with a speed of 140 m/s. If the bullet bounces straight back with a speed of 125 m/s, what is the change in momentum of the bullet?

**Chemistry**

A sample of gas has a mass of 0.555 g. Its volume is 119 mL at a temperature of 90 degrees C and a pressure of 744 mmHg. What is the molar mass of the gas?

**chemistry**

What volume of O2 at 912 mmHg and 33 degrees C is required to synthesize 11.0 mol of NO?

**Chemistry**

How many liters of O2 gas, measured at 772 mmHg and 20 degrees C, are required to completely react with 2.4 mol of Al?

**Chemistry**

What is 832 torr converted to atm?

**Chemistry**

What is 17.4 psi converted to atm?

**Chemistry**

What volume of O2 at 912mmHg and 33 degrees C is required to synthesize 11.0 mol of NO?

**Pharm Tech**

how many milliliters of a 5% stock solution are needed to prepare 250ml of a 2% solution?

**Chemistry**

If 1.0L of spilled 1M HCl needed to be neutralized using solid sodium carbonate, how many grams of solid would be required? a)53g b)106g c)1060g d)530g

**3rd grade**

what is the capital of brizil

**pre algerbra**

question: write the expression for a number used as a factor seventeen times being multiplied by the same number used as a factor fourteen times.then write the product as one power?

**mathematics**

it takes 12 men to make 12 tables in 9 hours. how long will it take 8 men to make 32 tables?

**physics**

A 40-kg cart moving at 120 km/h collides head on with an approaching 50-kg cart, moving at 20 km/h ( in the opposite direction). if the two carts stick together what will be their speed?

**Physics**

A block of wood is pulled by a horizontal string across a horizontal surface at a constant velotcity with a force of 20 N. What is the coefficient of kinetic friction between the surfaces?

**Physics**

A box weighing 600 N is pushed along a horizontal floor at a constant velocity with a force of 250 N parallel to the floor. What is the coefficient of Kinetic friction between the box and the floor?

**Physics**

thank you!

**Physics**

A 25-kg crate requires a horizontal force of 40 N to set it in motion. What is the coefficient of static friction between the crate and the floor?

**world history**

What distinguished the first centuries od Islamic history from the early history of Christianity and Buddhism? What simialrities and differences characterized their religious outlooks?

**geometry**

Describe a pattern in the numbers: 4, 6, 9, 13, 18

**chem 115**

1) here has been a great deal of controversy over whether cell phones cause brain cancer due to the emission of high energy waves near the head. The data on this is still being discussed (see NY Times article if you want more information) but we can do a simple calculation. ...

**chem 115**

The first ionization energy is the energy necessary to completely remove the outermost electron from an atom. For a Hydrogen atom this energy is 2.18 X 10^-18J. If you were to use a laser to provide this energy, what is the wavelength (in nm) of the light emitted from the laser?

**MAth**

630. i was confused about the rounding up or down of five.. some say down and some say up.

**MAth**

Round to the nearest hundred and the nearest tenth. 625

**Math**

Reasoning question... in order from least to greatest the six numbers whose digits are 2,8, and 9...

**english**

What is the theme of the poem A Kite is a Victim. What are juxtapositions in this poem

**poetry**

I am sorry could you give me a hint. I have read it over quite a few times. I still do not see where there are juxtapositions

**poetry**

Could you tell me how to go about analyzing or theme or poem "A Kite Is a Victim" by Leonard Cohen What are juxtapositions ?

**algebra 1**

(x+5)(x+2) (x-2)(x-2) (x+5)(x-12) (3c-4d)(2c+5d) (5x-3)(3x-8)

**math**

A rate is the increase between the time(seconds) and distance (meters).

**physics**

A 1000 kg boat is traveling at 90 km/h when its engine is shut off. The magnitude of the kinetic frictional force f_k between the boat and water is proportional to the speed v of the boat: f_k = 70v, where v is in meters per second and f_k is in newtons. Find the time required...

**chemisry**

Cd/Cd2+//H+/H2/Pt Write the oxidation and reductionhalf reactions. Sketch a possible deisgn cell. I am unclear on the Pt portion and the charges ?

**chemistry**

2H2O2 --- 2H2O + O2 is this a redox reaction if so what is the oxidized reactant and reduced reactant

**chemisry**

Two half cells in a galvanic cell consist of one iron electroide in a solution of iron sulphate and a silver electrode in a silver nitrate solution a) Assume that the cell is operating as a galvanic cell. State the oxidation half reaction, the reduction half reaction and the ...

**chemisry**

I am having problems with this redox question. 3 Ag2S + 2Al ---6 Ag + Al2S3 What are the charges on each;

**chemisry**

I am having problems with this redox question. 3 Ag2S + 2Al ---6 Ag + Al2S3 What are the charges on each;

**chemisry**

2NaHCO3 --- Na2CO3 + H2O + CO2 2Fe + 6 HCl -- 2 FeCl3 + 3H2 2HBr + Ca(OH)2 -- CaBr2 + 2H2O N2 + 3H -- 2NH3 2H2O -- 2H2O + O is this a redox ? what is oxidized, reduced

**Chemistry**

3Ag2S + 2 Al -- 6 Ag + Al2S3 State the charge on each ion in each of the comounds listed. I am having a hard time understanding how to do these redox questions

**chemistry**

a) show a balanced neutralization reaction for each. b) Determine how many moles of base are needed to neutralize 2 mles of acid of these reactions. Can you show me the work,using the mole ratio ?? HNO3 + KOH -- H2SO4 + NaOH --

**chemisry**

A technician needs to determine the concentration of lead ions in a sample of water a) Suggest a test chemical that can be added to the water sample to preciitate the lead ions. Show a chemical euation for the formation of the precipitate b) after a precipitate forms, it is ...

**chemistry**

I do not know where to start with this question. How can i find a substance that will form a precipitae with the lead. Could you suggest one and the possible formula

**chemistry**

A technician needs to determine the concentration of lead ions in a sample of water a) Suggest a test chemical that can be added to the water sample to preciitate the lead ions. Show a chemical euation for the formation of the precipitate b) after a precipitate forms, it is ...

**chemistry**

I thought I was to use a formula n=cXv. I had NaS c=.002 L V >01 mol/L Therefore I got NaS as .00002. So I had Na S as the limiting reagent

**chemistry**

2.00mL of 0.01 mol/L aqueous sodium sulphide is used to test a 50.omL sample of water containing 0.0005 mol/L mercury (II) nitrate ions. What mass of precipitate is formed? Na2S + Hg(NO3)2 --- 2NaNo3 + HgS determine limiting reactant using limiting reactant, calculate the ...

**chemistry**

what chemical test can be used to test for lead in water

**chemistry**

a contaminated water sample has a H of 3. How many times more acidic is this sample compared to neutral water of 7

**chemistry**

write a complete strucural formula for each reaction, Name the reactio and then the reactants and products C3H6 + Cl2 --- C3H6Cl2 NH3 + C4H9COOH---C4H9CONH2 + H2o C5H12 = O2 -- CO2 H2O

**chemistry**

Using structural formula, draw formulae illustrating the complete combustion of ethanol

**chemistry**

what two tests can I use to determine if a comound is an alcohol or a short or long chained carboxylic acid. I have two substances a colourless liquid and a white solid.

**Chemistry**

Please be specific. In an experiement 23.4 g of iron sulphide, FeS are added to excess oxygen, and 16.5 of Iron oxide, Fe2O3 are produced. The balanced euation for the reaction is 4FeS =7O2 -- 2Fe2O +2SO2. Calculate the percent yield of iron oxide in the experiment.

**chemistry**

I have posted this once and still cannot get the correct answer. Determine the mass of carbon monoxide that is produced when 45.6 of methane, CH4, react with 73.2 g of oxygen , O2. The products are carbon monoxide and water vapour.

**science**

What is a meteor mad out of?

**12th grade chemistry**

How do I prepare 500 ml of a .100 mol/L solution of copper sulphate.

**chemistry**

In an experiement 23.4 g of iron sulphide are added to excess oxygen and 16.5 grams of iron (III) oxide, Fe2O3 are produced the balanced equation for the reaction is 4FeS + 7O2 -- 2Fe2O3 + 2SO2 Calculate the percent yield of iron oxide in the experiement

**Chemistry**

Determine how many atoms there are in 1 litre of hexane or gasoline. A litre of gasoline has a mass of approximately 850.0 grams. Assume that the molecular formula for gasoline is C6H6

**Chemistry**

Determine how many atoms there are in 1 litre of hexane or gasoline. A litre of gasoline has a mass of approximately 850.0 grams. Assume that the molecular formula for gasoline is C6H6

**chemistry**

Determine the mass of carbon monoxide that is produced when 45.6 g of methane, ch4 react with 73.2 g of oxygen gas, o2. The products are carbon monoxide and water vapour