Friday

October 24, 2014

October 24, 2014

Total # Posts: 921

**Chemistry**

This is still not correct. I do not know what I am doing wrong
*October 23, 2014*

**Chemistry**

Suppose that 0.250mol of methane, CH4(g), is reacted with 0.400mol of fluorine, F2(g), forming CF4(g) and HF(g) as sole products. Assuming that the reaction occurs at constant pressure, how much heat is released? Substance ΔH∘f (kJ/mol) C(g) 718.4 CF4(g) −679....
*October 23, 2014*

**Chemistry**

I ended up with the wrong answer can I ask what I did wrong? So I got the dHrxn which I found to be -1,679.54 I then determined the limited reagent was indeed F2 and that it produced .1 mol of CF4 I then divided -1,679.54 by .1 to get -16,795.4 and converted it to kilojoules ...
*October 23, 2014*

**Chemistry**

Please help Suppose that 0.250mol of methane, CH4(g), is reacted with 0.400mol of fluorine, F2(g), forming CF4(g) and HF(g) as sole products. Assuming that the reaction occurs at constant pressure, how much heat is released? Substance ΔH∘f (kJ/mol) C(g) 718.4 CF4(g...
*October 23, 2014*

**Chemistry**

Thank you I ended up solving it right after I posted this. I wasn't factoring in the mas of the rod.
*October 23, 2014*

**Chemistry**

A volume of 100.mL of H2O is initially at room temperature (22.00 ∘C). A chilled steel rod at 2.00 ∘C is placed in the water. If the final temperature of the system is 21.50 ∘C , what is the mass of the steel bar? Use the following values: specific heat of ...
*October 23, 2014*

**math**

Find 1 terminating decimal and 1 repeating decimal between 1/2 and 2/3.
*October 21, 2014*

**Math HELP!!!!!**

give 2 examples of mixed numbers that when multiplied by 3/4 give a product between 3/4 and 1 PLEASE HELP ME AND QUICK I HAVE A LOT DUE TOMORROW!!!!!
*October 20, 2014*

**Math**

??????????????????????????????????????
*October 20, 2014*

**math**

if 1/2 times 3/4 is 3/8 why is it less than 3/4?
*October 20, 2014*

**physics**

a stone is dropped from the peak of a hill . IT covers the distance of 30m in last second of its motion. Find the height of the peak?
*October 12, 2014*

**Help Ms.Sue**

1/4 : 1/3 : 1 1/12 Can you simplify it with whole numbers?
*October 10, 2014*

**math help**

Is there a way to simplify it in numbers completely?
*October 10, 2014*

**math help**

(1+3 1/4) : (1 1/4 + 3 1/3) Simplify as a ratio?
*October 10, 2014*

**science**

yes sorry i mean krebs cycle. i just can't figure it out and I've looked everywhere in my book
*October 5, 2014*

**science**

Krebs Circle produces A)NADH and Carbon Dioxide B)ADP and NADP C)Acytol CoA and sugars D)Water and Carbon Dioxide
*October 5, 2014*

**Math**

Kate is 5 years older than Lenny. Lenny is 2 years younger than Maria. Maria is twice as old as Norman. If Norman is 10 years old, how old is katie?
*October 3, 2014*

**math**

if 2 chickens can lay 8 eggs in 3 days, how many eggs can 5 chickens lay in 6 days?
*October 3, 2014*

**math**

Help
*September 23, 2014*

**Physics**

Two telescopes A and B spot a star. Telescope A reports the position of the star to be in the East 60 degrees above the horizontal line joining A and B. Telescope B, which is 500 km West of telescope A spots the star at 30 degrees above the horizontal line joining A and B. ...
*September 18, 2014*

**Language Arts**

Which statement best expresses a central theme of the story teller? A. People with no children to care for are usually better at handling children. B. It is important to instruct children about right and wrong at all times. C. The best way for adults to deal with children is ...
*September 10, 2014*

**Physics**

The coefficient of rolling friction between the floor and the hardened steel balls of an anesthesia trolley (anesthesia machine with ventilator and monitor) is 0.0015. If a hospital crew needs 77 N to push the trolley at an angle of 30 degrees below the horizontal with ...
*September 10, 2014*

**math**

A merchant blends tea that sells for $4.40 a pound with tea that sells for $2.30 a pound to produce 120 lb of a mixture that sells for $3.00 a pound. How many pounds of each type of tea does the merchant use in the blend?
*September 7, 2014*

**math**

A college student earned $8900 during summer vacation working as a waiter in a popular restaurant. The student invested part of the money at 10% and the rest at 9%. If the student received a total of $831 in interest at the end of the year, how much was invested at 10%?
*September 1, 2014*

**Math**

How do you expand and simplify (x-2)(x+2)?
*August 8, 2014*

**physics**

A sprinter has a mass of 82.0 kg. If the sprinter is running at a speed of 22.5 km/h, determine his kinetic energy. __________ × 103 J.
*July 31, 2014*

**physics**

A 130.0 g object is moved from a shelf 0.2 m high to one that is 5.0 m high. The change in potential energy for the object is __________ .
*July 31, 2014*

**physics**

A hockey player lifts a 600 g trophy up into the air a distance of 75.0 cm. The work done against gravity on the trophy is __________ J.
*July 31, 2014*

**physics**

When an object travelling at 12.7 m/s [E] speeds up to a velocity of 21.5 m/s [E] in 3.45 s, the magnitude of the acceleration is __________m/s2.
*July 31, 2014*

**Life sciences**

So no one can take it/Security. They're pretty rare. Is this supposed to be written in a paragraph though?
*July 31, 2014*

**Mathh**

Thanks alot.
*July 31, 2014*

**Mathh**

After Michael 110 baseball cards to Sally and 75 to Heidi, he still has 315 left. What percent of his cards did Michael give away? 110 + 75... and then??
*July 31, 2014*

**Math**

No. 500% is right. I tried it on my online homework. Thanks :)
*July 31, 2014*

**Math**

Umm, isn't it 5000? :)
*July 31, 2014*

**Math**

Thank you
*July 31, 2014*

**Math**

If the investment rises from $1000 to $5000, the percent is what from the original?
*July 31, 2014*

**science**

A mass m=5.2 kg is attached to the end of a spring with a spring constant of k=15.6 N/m. The mass moves through a viscous damping medium with a damping constant b=1.8 kg/s giving a velocity dependent damping force Fdamp= -bv. The motion occurs in zero gravity so set the force ...
*July 23, 2014*

**statistics**

M&M’s The candy company claims that 10% of the M&M’s it produces are green. Suppose the candies are packed at random into small bags containing about 25 M&M’s per bag. A class of elementary students learning about percentages opens several bags, counts the ...
*July 13, 2014*

**USA Colonists History**

thx, but what about the land?
*June 13, 2014*

**USA Colonists History**

i think that 1. They could trade the things they dig, find and then sell it. 2. They could make materials from the trees they find, etc., and sell them.
*June 13, 2014*

**Math**

James takes a ruler and measures the width of the piece of paper. He find that the actual width is 48.8 cm. Find the width of each strip.
*May 28, 2014*

**math **

A new cruise ship line has just launched 3 new ships: the Pacific, the Caribbean, and the Mediterranean. The Caribbean has 32 more rooms then the Pacific. The Mediterranean has 38 fewer rooms than FOUR times the number of rooms on the Pacific. Find the number of rooms for each...
*May 20, 2014*

**English**

> rain's <
*May 20, 2014*

**math**

thanks
*May 20, 2014*

**math**

the value is 56 my bad
*May 20, 2014*

**math**

The value of an uncirculated mint state-65 1950 jefferson nickle minted in denver is 4/3 the value a 1945 nickle minted in philadelphia is similar condition. together the total value of the two coins is $21.00
*May 20, 2014*

**calculus**

Consider the motion of a particle of mass m falling vertically under the earth’s gravitational field, and suppose the downward motion is opposed by a frictional force p(v) dependent on the velocity v(t) of the particle. Then the velocity satisfies the equation mv0(t) = &#...
*May 18, 2014*

**Math**

Please can someone help?
*May 5, 2014*

**networks**

what method can be used to reduce packet jitter
*May 1, 2014*

**networks**

Sorry but what causes packet jitter
*May 1, 2014*

**alg.**

Solve. (If there is no solution, enter NO SOLUTION.) y= x^2-x-4 y=x+4 (x, y) = ( , ) (smaller x-value) (x, y) = ( , ) (larger x-value) x^2 + y^2 =10 x+y=4 (x,y)= ( , ) smaller value (x,y)= ( , ) larger value
*April 22, 2014*

**Accounting**

Target Company issues bonds with a par value of $900,000 on their stated issue date. The bonds mature in 10 years and pay 10% annual interest in semiannual payments. On the issue date, the annual market rate for the bonds is 12%. What is the selling price of the bond
*April 15, 2014*

**school**

give me the answer!
*April 12, 2014*

**math - 6th grade**

4x+2=3x+9 Move 3x to the other side so it will become -3x ( 4x-3x) same with the constant number ( 9-2) . Just combine the constant and the number that has coefficient. Solution: 4x+2= 3x+9 4x-3x=9-2 X=7
*April 3, 2014*

**physics**

Eva is in a closed, dark room. She uses her arm muscles to turn on a lamp. When she moves her hand closer to the lamp, the light heats her hand. The light bounces off the pages of a book and into her eyes. If this room is a closed system, what happens to the total amount of ...
*March 29, 2014*

**urgent (physics)**

A 2 kg brick falls at 5.1 m/s from a height of 6 m above a spring that has a spring constant of 47 N/m. The brick strikes and compresses the spring until it stops moving. Ignore friction effects. How much is the spring compressed by the brick? Assume that there is no Eg after ...
*March 14, 2014*

**Physics**

A 2 kg block has an initial velocity of 16 m/s at the bottom of the ramp (see diagram below). The coefficient of kinetic friction between the block and the ramp is 0.1. The spring has length 3 m and has a spring constant of 100 N/m. What maximum compression will the spring ...
*March 9, 2014*

**Alegbra 1**

Explain why any two regular n-sided polygons would be considered to be similar and how knowing this information could help in solving real-world problems.
*March 3, 2014*

**Math**

what is a measurement that is not equal to 8 cups?
*March 3, 2014*

**Biology**

Which of the following is correctly matched with its tissue system? cortex/dermal tissue system cuticle/vascular tissue system phloem/dermal tissue system stele/vascular tissue system>>>> my choosen answer
*February 28, 2014*

**math**

17.Given that 3•2 = 9, 2•6 = 64, 1•7 = 1 and 4•4 = 256. What is the value of 10•5? A)50 B)100 000 C)5000 D)5 plz explain how you get this answer i am studying the sample questions for the math olympics tommorow so i need to know what they will be like.
*February 26, 2014*

**physics**

A missile is launched at an angle of 25 degrees to the ground. It hits a target at 301.5 meters from the point of launch. find the initial velocity
*February 22, 2014*

**Physics**

A 14g bullet is traveling at 306m/s when it strikes a block of wood. If the block of wood exerts a force of 50,000 N opposing the motion of the bullet, how far will the bullet penetrate the block of wood?
*February 20, 2014*

**Chemistry**

Calculate the Ph and POH of an aqueous soltuion that is 0.500 M in HCl(aq) and 0.085 M in HBr (aq) at 25 degrees C.
*February 20, 2014*

**Physics**

A 2473 kg elephant is walking at 3 m/s on a flat surface. How much kinetic energy does he have? Answer in Joules
*February 17, 2014*

**still need help on this one**

...
*February 17, 2014*

**Physics**

A 2473 kg elephant is walking at 3 m/s on a flat surface. How much kinetic energy does he have? Answer in Joules or J
*February 17, 2014*

**Math**

Identify the zeros, vertex and axis of symmetry of y=-1/3(x+7)(x+1)
*February 13, 2014*

**Physics**

A 254kg box is pulled at a constant speed by the little engine. The box moves a distance of 3.0 m across the horizontal surface. (μ=.20) How much energy is transferred by the engine? (How much WORK is done?) what is the answer in joules?
*February 13, 2014*

**Physics**

The above spring has a spring constant of 29 N/m. The μ between the box and the surface is 0.3. The box has a mass of 1 kg. What is the maximum distance that the spring can be stretched from equilibrium before the box begins to slide back?
*February 12, 2014*

**Chem **

S2 + C ----> CS2 How many grams of CS2 can be prepared by heating 11.0 moles of S2 with excess carbon in 5.20 L reaction vessel held at 900 kelvin until equilibrium is attained? Kc= 9.40
*February 10, 2014*

**science**

Can scientists use radiocarbon dating to find the age of a very tall, old redwood tree living in an old growth forest? Explain your answer.
*February 10, 2014*

**Chemistry**

sorry, didnt mean to post twice lol computer glitched XD
*February 5, 2014*

**Chemistry**

Answer the following questions about the characteristics of the elements in Group 2 (the alkaline earths). How do they react with iodine? How do they react with water? How do they react with oxygen? Which reacts the most vigorously? Which element in the group is the most ...
*February 5, 2014*

**Statistics **

What I mean by a "running number" is that the average is always changing. If I turn in 10 homework assignments and the grades are as follows: 58, 87, 99, 90, 92, 95, 89, 90, 95, 91 then my average is 88.6. If I turn in 10 more assignments my average changes, we don&#...
*January 26, 2014*

**statistics**

when will I know it is time to calculate the mean? Is the mean a running number?
*January 25, 2014*

**statistics**

do we need to calculate z in order to use the critical value like we did when we calculated the p value?
*January 20, 2014*

**Hypothesis test **

Please explain the solution to this problem. Individuals filing federal income tax returns prior to March 31 received an average refund of $1056. Consider the population of "last-minute" filers who mail their tax return during the last five days of the income tax ...
*January 18, 2014*

**Geometry Proofs (w/Pic)**

If PQRS is a rectangle and M is the midpoint of RS, prove PM is congruent to QM. P----------------Q |\ /| | \ / | | \ / | | \ / | | \ / | R--------M-------S *be as explanatory as possible
*January 18, 2014*

**Math**

The number of peaches, p, is three less than half the number of grapes, g. Which expression represents the number of peaches in terms of the number of grapes?
*January 17, 2014*

**English**

I think d because a broadcaster uses a microphone
*December 6, 2013*

**English**

Oh ok I understand now so I would say 1.a 2.a 3.c
*December 6, 2013*

**English**

Select the letter of the pair of words that expresses a relationship expressed by the following pair 1.Stethoscope:doctor a.manager: trainee b.best-seller: publisher c.tool:shovel d.microphone:broadcaster 2.cubism:art a.dictatorship:government b.suit:vest c.bravery:fear d....
*December 6, 2013*

**English**

Thanks for your help
*December 6, 2013*

**English**

1.a 2.d 3.d
*December 6, 2013*

**English**

Select the letter of the pair of words that expresses a relationship expressed by the following pair 1.Stethoscope:doctor a.manager: trainee b.best-seller: publisher c.tool:shovel d.microphone:broadcaster 2.cubism:art a.dictatorship:government b.suit:vest c.bravery:fear d....
*December 6, 2013*

**Statistics**

Of the parts produced by a particular machine, 1.5% are defective. If a random sample of 11 parts produced by this machine contains 2 or more defective parts, the machine is shut down for repairs. Find the probability that the machine will be shut down for repairs based on ...
*November 30, 2013*

**Statistics**

paired test hard
*November 21, 2013*

**math**

The Robinson come from three states of the country. 6 of them come from Minnesota. The rest come from Texas and Florida. There are 5 more family members from Texas than from Florida .how many Robinson comes from each state?
*November 18, 2013*

**math**

The Robinson come from three states of the country. 6 of them come from Minnesota. The rest come from Texas and Florida. There are 5 more family members from Texas than from Florida .how many Robinson comes from each state?
*November 18, 2013*

**math**

The Robinson come from three states of the country. 6 of them come from Minnesota. The rest come from Texas and Florida. There are 5 more family members from Texas than from Florida .how many Robinson comes from each state?
*November 18, 2013*

**math**

The Robinson come from three states of the country. 6 of them come from Minnesota. The rest come from Texas and Florida. There are 5 more family members from Texas than from Florida .how many Robinson comes from each state?
*November 18, 2013*

**Science - The Sun**

What is the true thickness of each of the sun's layers (core, radiation zone, convection zone, photosphere, chromosphere, and corona)? What is the age, composition, average density, period of rotation, distance from Earth, and source of energy from the sun?
*November 7, 2013*

**Math**

0.04m + F = 12
*November 7, 2013*

**physics**

How much power must you exert to horizontally drag a 21.0kg table 15.0m across a brick floor in 20.0s at constant velocity, assuming the coefficient of kinetic friction between the table and floor is 0.500?
*October 24, 2013*

**physics**

A pump lifts 200kg of water per hour a height of 6.0m . Part A What is the minimum necessary power output rating of the water pump in watts? Part B What is the minimum necessary power output rating of the water pump in horsepower?
*October 24, 2013*

**physics**

Two workhorses tow a barge along a straight canal. Each horse exerts a constant force of magnitude F, and the tow ropes make an angle θ with the direction of motion of the horses and the barge. (Figure 1) Each horse is traveling at a constant speed v. How much work W is ...
*October 24, 2013*

**physics**

You are a member of an alpine rescue team and must get a box of supplies, with mass 3.00kg , up an incline of constant slope angle 30.0∘ so that it reaches a stranded skier who is a vertical distance 2.90m above the bottom of the incline. There is some friction present; ...
*October 24, 2013*

**stats**

An investment broker reports that the yearly returns on common stocks are approximately normally distributed with a mean return of 12.4 percent and a standard deviation of 20.6 percent. On the other hand, the firm reports that the yearly returns on tax-free municipal bonds ...
*October 3, 2013*

**health**

what are some mental or emotional problems i can research
*October 1, 2013*

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