Friday

February 12, 2016
Total # Posts: 679

**Physics**

A merry-go-round is a common piece of playground equipment. A 6.42m diameter merry-go-round with a mass of 648.0kg is spinning at 39.4rpm. John runs tangent to the merry-go-round at 6.36m/s, in the same direction that it is turning, and jumps onto the outer edge. John's ...
*January 26, 2016*

**Math**

Let f(t)=t^(2)+5t+2. Find a value of t such that the average rate of change of f(t) from 0 to t equals 11. t=
*January 21, 2016*

**Maths**

i'm thinking of a number that has two tenths, twice as many hundredths as tenths, half as many hundreds as tenths, twice as many tens as hundreds and three times as many ones as hundredths. Can you Guess the number
*January 19, 2016*

**MAth GCF LCM**

25 square floor mats in a gymnasium are connected together to form a large square area of 22500 cm². What is the length of the side of each square floor mat?
*January 6, 2016*

**math**

A box contains 18 marbles, 8 red, 4 green, & 6 white. What is the smallest number of marbles that must be selected to have one of each color marble?
*December 16, 2015*

**Math**

Over the past week, 34 baby boys were born at the hospital. This was 54% of all babies born. How many girls were born over the past week?
*November 20, 2015*

**Trig right triangle**

can i also have the actual answer and the process
*November 17, 2015*

**Trig right triangle**

A ship leaves port at 6 am and heads due east at 20 knots. At 10 am, to avoid a storm the ship changes course to N 47°. Find the ships distance from port at 4 pm.
*November 17, 2015*

**Math**

Just learned log rules and I don't get it. How do you solve log5x^2 + 4log5x = 12 ? Thanks in advance.
*October 28, 2015*

**AP Chemistry**

For each of the following pairs of half-cells, determine the overall electrochemical reaction that proceeds spontaneously. Na+ | Na, Ni2+ | Ni
*October 26, 2015*

**Chemistry **

Why is it important to not let the wooden split burn ?
*October 23, 2015*

**Algebra 2**

Give one example of a situation where you would make a discrete graph and an example of when you will see a continuos graph . I need help pls
*October 21, 2015*

**Algebra 2**

Give one example of a situation where you would make a discrete graph and an example of when you will see a continuous graph.
*October 21, 2015*

**Algebra 2**

3x/7+2/7=2
*October 13, 2015*

**Algebra 2**

(4.3,-2.3) is it correct
*October 13, 2015*

**Algebra 2**

Solve the following systems algebraic ally X+2y=17 X-y=2
*October 13, 2015*

**Math**

7 cups
*October 12, 2015*

**Algebra 2**

Jason loves to download music. Downloads R Us sells songs only in packages of three, and it charges $2.00 for each package of three songs. Jason's favorite group just released their greatest hits CD, which has 17 songs on it. Jason wants to buy all 17 songs from downloads ...
*September 12, 2015*

**Chemistry**

ClO- + I- → IO- + Cl- 1) What are the names of these ions? is it "The hypochlorite ion reacts with iodide ion to form iodate ion with chloride ion" ? 2) Write the general rate law (using the letters k for the rate constant, and n and m for the reaction orders...
*September 7, 2015*

**chemistry**

Hydrogen sulfide burns in oxygen to form sulfur dioxide and water. If sulfur dioxide is being formed at a rate of 0.19 mol L-1 s-1, what are the rates of disappearance of hydrogen sulfide and oxygen? rate of disappearance of O2? rate of disappearance of H2S? I got : rate of ...
*September 4, 2015*

**chemistry**

The radioactive isotope, phosphorus-32, has a half-life of 14.26 days. How much phosphorus-32 will remain after 60 days? Please help.
*September 3, 2015*

**chemistry**

@DrBob222 for number 2, is it 1.09x10^-4*1/3?
*September 1, 2015*

**chemistry**

ClO3^-(aq)+3SO3^2- ¡÷ Cl^-(aq)+3SO4^2- 1) If the SO3^2- ion is disaapearing at rate of 0.458 mol/L*s, how fast is the Cl^- ion appearing? 2) if the after 10 minutes of reaction time, 1.09x10^-4 mole of Cl^- ion has been produced, how many moles of SO3^2- ion have ...
*September 1, 2015*

**Algebra**

How do I rearrange this equation to solve for m1 (step by step) r1/r2 = √m2/m1
*August 24, 2015*

**World History**

Why did Mesopotamia city-states flourished? Was it due to specialized labor or conquered an area large enough to make themselves self-sufficient.
*August 8, 2015*

**Physics**

A 10.0-m long wire whose total mass is 39.5 grams is under a tension of 577 N. A pulse is sent down the left end of the wire and 29 ms later a second pulse is sent down the right end of the wire. Where do the pulses first meet?
*July 21, 2015*

**chemistry**

1. Which example has particles that can be drawn closer to occupy smaller volume? a. fruit juice b. block of wood c. air inside the syringe d. ice cube 2. Which of the following phenomena does NOT involve the application of gas pressure? a. burning fuels b. falling leaves c. ...
*July 10, 2015*

**chemistry**

A piece of iron (Cp = 0.450 J/(gi°C)) that has a mass of 21.5 g and an initial temperature of 100.0°C is submerged in X g of water (Cp = 4.184 J/(gi°C)) at 20.0°C. The temperature of the system (iron and water) changes to 21.4°C. What is the value of X?
*July 7, 2015*

**chemistry**

1. Which example has particles that can be drawn closer to occupy smaller volume? a. fruit juice b. block of wood c. air inside the syringe d. ice cube 2. Which of the following phenomena does NOT involve the application of gas pressure? a. burning fuels b. falling leaves c. ...
*July 6, 2015*

**math**

2 trains leave metropolos at same, one going south 50 mph the other east 40 mph. How far apart will they be at 3 hours
*June 3, 2015*

**calculus**

Can I have a website of Beginner calculus books?
*June 2, 2015*

**Finite Math**

Thanks
*April 6, 2015*

**Finite Math**

P(R or S)=.64 P(R)=.38 P(S)=.52 Probability Union Rule P(R and S)=P(R)+P(S)-P(R and S) .64=.38+.52-P(R and S) .54=.9-P(R and S) At this point, how do I deal with the -P(R and S)? I know the final answer is .26, but how do I get there?
*April 6, 2015*

**Chemistry**

Cola drinks have a phosphoric acid content that is described as `from 0.057% to 0.084% of 75% phosphoric acid, by mass." Estimate the pH range of cola drinks corresponding to this average range of H3PO4 content. I am having trouble with the wording of this question, I ...
*February 3, 2015*

**math**

a 150g-iron ball at 95 Celsius is dropped into a cavity in a block of ice.the cavity is then found to contain 21 g of water . CALCULATE THE HEAT OF FUSION OF ICE (The specific heat capacity of iron is 0.11 cal/g x C degrees.)
*January 27, 2015*

**math**

so the answer would be 305.36 J/G ? is that right?
*January 27, 2015*

**math **

a 150g-iron ball at 95 Celsius is dropped into a cavity in a block of ice.the cavity is then found to contain 21 g of water . calculate the heat of fusion of ice.
*January 27, 2015*

**Math**

Thanks
*January 26, 2015*

**Math**

I need help, thanks
*January 26, 2015*

**Math**

I re did it 4/5
*January 26, 2015*

**Math**

1/80
*January 26, 2015*

**Math**

Is the answer is a<5/4
*January 26, 2015*

**Math**

I cross multiply by 10/6
*January 26, 2015*

**Math**

-3/4>-6/10a a>2/5 my answer
*January 26, 2015*

**Chemistry**

What is the HCl concentration if 65.8mL of 0.300M NaOH is required to titrate a 15.0mL sample of the acid?
*December 18, 2014*

**science 8**

Waht is the reason for the seasons experiment?
*December 16, 2014*

**chemistry**

50ml of 20.8% bacl2 and 100ml of 9.8% h2s04 solutions are mixed. Molarity of cl ions in the resulting solution wt of ba =137 I do not still understand step by step clearly Thank a lot
*November 23, 2014*

**chemistry Thank a lot help**

100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final density 1.25g/ml. 50ml of 20.8% bacl2 and 100ml of 9.8% h2s04 solution are mixed. Molarity of cl ions in the resulting solution is ...
*November 22, 2014*

**Math**

30 cm
*November 20, 2014*

**chemistry **

100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final density is 1.25g/ml 50ml of 20.8% bacl2 and 100ml of 9.8% h2s04 solutions are mixed. Molarity of cl ions in the resulting solution ...
*November 16, 2014*

**chemistry Ben **

50ml of 20.8% bacl2 and 100ml of 9.8% h2s04 solutions are mixed. molarity of cl ions in the resulting solutions is At.wt of ba = 137 100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final...
*November 16, 2014*

**chemistry step by step for me**

100ml of h2s04 solution having molarity 1M and density 1.5g/ml is mixed with 400ml of water. Calculate final molarity of h2s04 solution if final density is 1.25g/ml. 50ml of 20.8% bacl2 and 100ml of 938% h2s04 solutions are mixed. Molarity of cl ions in the resulting solutions...
*November 16, 2014*

**math**

plot the number on the number line 1 5/6
*October 22, 2014*

**math**

A wheel made 660 revolutions at 44 8/9 revolutions per minutes. how many minutes did it rotate
*October 21, 2014*

**English - Parts of Speech**

I want the definition of all Parts of Speech(not too short, not too long) with five examples. Thanks in advance.
*October 2, 2014*

**English**

What are the different parts of speech?
*September 28, 2014*

**Algebra**

Please show how to solve for problems like this: How many pounds of coffee that costs 4.50/lb be mixed with 20 lbs of coffee that costs 7.50/lb to make a mixture that costs 5.00/lb
*September 22, 2014*

**Science**

When taking a bath, we use approximately 450 lbs of water. How much heat, measured in British Thermal Units (BTU) is required to heat the water from 60 degrees Fahrenheit to 104 degrees Fahrenheit?
*September 9, 2014*

**Chem**

A 2.8L engine in a vehicle with air conditioning uses 26.5L of coolant. If the coolant has density of 1.11g/ml, what mass does the coolant add to the vehicle ?
*September 2, 2014*

**chemistry clearly step by step**

Al2(s04)3 solution of 1 molal concentration is present in 1 litre solution of 2.684g/cc.How many moles of bas04 would be precipitation on adding bacl2 in excess? The answer 6M I do not understand pls explain step by step Thank a lot all tutors
*July 20, 2014*

**chemistry step by step clearly**

10L of hard water required 5.6g of lime for removing hardness. hence temporary hardness in ppm of cac03. The answer 1000ppm I really want all tutors to solve it form clearly step by step. Thank a lot
*July 20, 2014*

**chemistry step by step for me. Thank a lot**

342gm of 20% by mass of ba(oh)2 solution sq gr .57 is reacted with 1200ml of 2m hn03. if the find density is same as pure water then molarity of the ion in resulting solution by nature of the above solution is dentified. The answer 0.888M Who helps me to solve it step step ...
*July 19, 2014*

**Chemistry step by step thank a lot**

10L of hard water required 5.6g of lime for removing hardness. Hence temporary hardness in ppm of cac03 The answer 1000 Who helps me to solve it for me step by step clearly Thank a lot all tutors
*July 13, 2014*

**chemistry step bystep thank a lot**

10L of hard water required 5.6g of line for removing hardness. Hence temporary hardness in ppm of cac03. The answer 1000 ppm= 1mg/1L cac03 = 100 g/mol who solve it for me clearly step by step Thank a lot all tutors
*July 12, 2014*

**chemistry step by step for me clearly**

Al2(s04)3 solution of a molal concentration is present in 1 litre solution of 2.684g/cc. How many moles of bas04 would be precipitated on adding bacl2 in excess. The answer 6M I want some tutors to explain for me step by step clearly. I do not still understand Thank a lot all ...
*July 12, 2014*

**chemistry step by step thank a lot**

Al2(s04)3 solution of a molal concentration is present in 1 litre solution of 2.684g/cc. How many moles of bas04 would be precipitated on adding bacl2 in excess? the answer 6M Who helps me step by step for me clearly I am thankful to all tutors
*July 11, 2014*

**chemistry step by step for thank a lot **

10L of hard water required 5.6g of lime for removing hardness. Hence temporary hardness in ppm of caco3. The answer 1000 who helps me to solve it for me step by step thank a lot
*July 6, 2014*

**chemistry step by step for me thank a lot **

What is the weight of ca(oh)2 required for 10 litre of water remove temporary hardness of 100 ppm due to ca(H03)2 The answer 0.74 Thank all tutors for your help Pls show step by step for me
*July 6, 2014*

**chemistry step by step thank a lot**

342gm of 20% by mass of ba (OH)2 solution sq gr 0.57 is reacted with 1200ml of 2M hn03. If the final density is same as pure water then molarity of the ion in resulting solution by nature of the above solution is dentified 0.888m Who solve it for me step by step thank a lot
*July 6, 2014*

**chemistry step for step thank a lot **

10L of hard water required 5.6g of lime for removing hardness. Hence temporary hardness in ppm of cac03. The answer 1000 I think ppm= 1mg/1L 10L x 100g/mol cac03 = 1000 Who check it for me step by step Thank all tutors for your help. How many ml of a 0.05M kmno4 solution are ...
*July 5, 2014*

**Chemistry step by step thank a lot**

10L of hard water required 5.6g of line for removing hardness. hence temporary hardness in ppm of cac03. The answer is 1000 Pls solve it for me step by step Thank a lot all tutors for your help.
*July 5, 2014*

**chemistry Step for step for me thank a lot**

A sample of peanut oil weighing 2g is added to 25ml of 0.4M koh. After saponification is complete, 8.5ml of 0.28M hes04 is needed to neutralize excess of koh. The saponification number of peanut oil I do not still understand Pls clearly step by step for me. Thank a lot The ...
*July 4, 2014*

**Chemistry Step by step for me Thank a lot**

A sample of peanut oil weighing 2g is added to 25ml of 0.4M koh. After saponification is complete, 8.5ml of 0.28M hes04 is needed to neutralize excess of koh. Saponification number of peanut oil Thank for all tutors for your help. Pls solve it for me step by step for me. The ...
*July 4, 2014*

**chemistry step by step for me Bob**

A sample of peanut oil weighing 2g is added to 25ml of 0.4M koh. After saponification is complete, 8.5ml of 0.28M hes04 is needed to neutralize excess of koh. The saponification number of peanut oil. The right answer 146.75 Bob solve it for me step by step
*July 4, 2014*

**chemistry Ben step by step for me**

10L of hard water required 5.6g of lime for removing hardness. Hence temporary hardness in ppm of cac03 The answer 1000 I do not get answer 1000 ppm= 1mg/1L Ben solve it for me step by step for me
*July 4, 2014*

**chemistry please step by step for me**

what volume of hcl solution of density 1.2g/cm3 and containing 36.5% by weight hcl, must be allowed to react with zinc in order to liberate 4g of hydrogen I know this calculate this part, but I do not get the answer 333.3ml 1.2g/ml x 1000 x 0.365/36.5 = 12M or other ...
*July 4, 2014*

**chemistry**

What volume of hcl solution of density 1.2g/cm3 and containing 36.5% by weight hcl, must be allowed to react with zinc in order to liberate 4g of hydrogen The answer 333.3ml Who helps me step by step for me
*July 4, 2014*

**chemistry**

one litre of a sample hard water contain 4.44mg cacl2 and 1.9mg of mgcl2. What is the total hardness in terms ppm of cac03?
*June 29, 2014*

**chemistry Who clearly step by step**

What per cent of free s03 can be obtained from 100g oleum, that is labeled with 113.5% h2s04? To 100 ml of 5M naoh solution density 1.2g/ml were added 200ml of another naoh solution with have a density 1.5g/ml and contains 20 mass percent of naoh. What is the concentration of ...
*June 29, 2014*

**chemistry who step by step for me**

1.2g mixture of na2c03 and k2c03 was dissolved in water to form 100cm3 of solution, 20 cm3 of this solution required 40cm3 of 0.1 hcl for neutralization. Calculate the weight na2c03 and k2c03 in the mixture? My calculation 20cm3/100cm3 = 0.2 x/53 + (0.2g-X) + y/69 = 0.004 0....
*June 22, 2014*

**pharmacy math who helps me step by step for me**

How much 30% alcohol, 45% alcohol, 60% alcohol and 95% alcohol could be mixed to make 200ml of alcohol? the right answer 30% is 112.5ml 45% is 25ml 60% is 12.5ml 95% is 50ml Who helps me step by step clearly Please some professional tutor solve it
*June 22, 2014*

**chemistry step by step for me **

0.6g mixture of licl and bal was treated with 40ml of 0.2N agn03 and the excess ag on titration required 25ml of 0.1N kcns for the end point using ferric alum as the indicator. What is the percentage of iodine in the mixture Who helps me step by step for me clearly
*June 22, 2014*

**Chemistry pls clearly step step for me **

2gm of mixture hydrated sodium carbonate and sodium bicarbonate was dissolved in water and made up to 250cc. 25cc of this solution was titrated using methyl orange as indicator and 22.5cc of 0.087N hcl were required for naturalization. calculate the percentage of sodium ...
*June 21, 2014*

**chemistry Please who helps me stpe by step**

2gm of mixture hydrated sodium carbonate na2c03 /OH20 and sodium bicarbonate was dissolved in water and made up to 250cc. 25cc of this solution was titrated, using methyl orange as indicator and 22.5cc of 0.087N hcl were required for neutralization. Calculate the percentage of...
*June 21, 2014*

**Chemistry Who step by step **

A 0.8870g sample of a mixture of nacl and nan03 is dissolved in water, and the solution is then treated with an excess of AGN03 to yield 1.913g of agcl. Calculate the percent by mass of the nacl in the mixture. 1.913g / 143 = 0.0133 x/58 ( 0.8870g -x) y/85 = 0.0133 0.01529 - 0...
*May 11, 2014*

**physics**

a particle of mass m moving with a speed v meters per second strikes a particle of mass 3m at rest and joins together. express the final kinetic energy as a fraction of initial energy
*May 5, 2014*

**physics**

when a force of 0.245 newtons is applied to a body of mass 250g which is resting on a horizontal plane, the body is found to be in a limiting equilibrium. find the coefficient of friction between body and planes.
*May 5, 2014*

**physics**

a body of mass 5kg falls vertically against a resistance of x Newtons.The body passes through two points A and B, 2.5 METERS APART with A above B, WHEN TRAVELING WITH SPEED 2 METERS PER SECOND AND 6 METERS PER SECOND RESPECTIVELY. BY ENERGY CONSIDERATION , FIND THE VALUE OF X.
*May 5, 2014*

**physics**

in every minute a pump draws 6 metric cubed of water from a well and issues it at a speed of 5 meters per second from the nozzle situated 4 meters above the level from which the water was drawn. find the average rate at which the pump is working. (1 metric cubed =1000kg)
*May 5, 2014*

**physics**

a hot air ballon rises from the ground with a uniform acceleration. after 10 seconds the ballon has attained a height of 25 metres. if the total mass of ballon and its bucket is 250 kg, find the magnitude of the force f
*May 5, 2014*

**algebra**

given that sin (2x+30)=cos(x-15).determine the value of x given x is an acute angle
*April 25, 2014*

**French**

travaille dans un magasin. ( rewrite the article and the noun) The salesclerk
*April 20, 2014*

**physics**

Don't you need either angle of the string or mass of plane or velocity to answer this question?
*February 21, 2014*

**physics**

If a toy plane is spinning on a string 1.87 meters off the ground and the string is .5m long how long does it take to make 10 revolutions?
*February 21, 2014*

**physics**

Calculate the pressure exerted on the floor by the heel if it has an area of 1.45 cm2 and the woman's mass is 58.0 kg. Express the force in N/m2 and lb/in
*February 3, 2014*

**Maths**

Wendy has 80 more stamps than Mary but 50 more stamps than Jean. Wendy gives 1/2 of her stamps to Mary. Then Mary gives 1/5 of her stamps to Jean. If Jean has 62 more stamps than Wendy, how many stamps does Mary have in the end?
*December 30, 2013*

**MATHS**

Judy is given some money to buy files. If she buys 5 files, she will have $4 left. If she buys 9 files, she will need another $5. How much money does she have?
*December 30, 2013*

**physics**

A firework rocket is launched vertically from rest and loses 60% of its mass during a burn time of 4 seconds. What is the final speed of the rocket relative to the ground (in m/s) when the gas relative to the rocket has a speed v= 80 m/s? a. 15 m/s; b. 34 m/s; c. 68 m/s; d. ...
*December 29, 2013*

**solar energy please help**

c)Because the voltage difference created in the photoelectrode is not able to produce enough voltage to drive the reaction c 1.43V
*November 6, 2013*