Thursday

February 11, 2016
Total # Posts: 917

**physics**

A car traveling at 150 miles/hour strikes a wall and bounces backwards at 30 miles/hour. If the car is in contact with the wall for 0.1 seconds, what is the force that the car exerts on the driver.
*March 24, 2013*

**Chemistry**

How many milliliters of 6.50 M HCl(aq) are required to react with 5.95 g of an ore containing 35.0% Zn(s) by mass?
*March 20, 2013*

**science**

How does the hierarachical organization of organisms work within a system?
*March 20, 2013*

**Chemistry**

59.0 mL of a 1.80 M solution is diluted to a total volume of 268 mL. A 134-mL portion of that solution is diluted by adding 171 mL of water. What is the final concentration? Assume the volumes are additive.
*March 19, 2013*

**Chemistry**

How many milliliters of 11.5 M HCl(aq) are needed to prepare 310.0 mL of 1.00 M HCl(aq)?
*March 19, 2013*

**math(statistics)**

1. Assume that x is a binomial variable with an expected value of 3 and variance of 2.4 .find (a) P(x=0) (b) P(x=12) THnxs
*March 19, 2013*

**english**

Write the pronoun in these sentences. Then write the underlined words,that they replace. " Let us think of a way to clean up litter," said Matt and Lynn. ( the underlined word is Matt and Lynn)
*March 18, 2013*

**median help**

Pat recorded the weights of the first ten fish she caught and released at Mirror Lake this season. The weights were 8 lb, 6 lb, 9 lb, 6 lb, 7 lb, 5 lb, 7 lb, 6 lb, 23 lb, and 6 lb. What is the median of the data set
*March 8, 2013*

**math help**

please help
*March 8, 2013*

**math help**

Pat recorded the weights of the first ten fish she caught and released at Mirror Lake this season. The weights were 8 lb, 6 lb, 9 lb, 6 lb, 7 lb, 5 lb, 7 lb, 6 lb, 23 lb, and 6 lb. What is the median of the data set
*March 8, 2013*

**Chemistry**

1.) A 3.000gram sample of a hydrate compound containing Co, C2O4, and H2O was combusted to give 1.316g of Co3O4. What is the percentage of Cobalt in the oxide? 3.) 2.000 grams of a sample containing Co, C2O4, and H2O showed there to be 0.9621g of oxalate in the sample. Was is...
*March 3, 2013*

**physics **

A girl whirls a stone in a horizontal circle 1.5 m above the ground by means of a string 141 cm long. The string breaks, and the stone flies of horizontally and strike the ground 13.6 m away. What is the centripetal acceleration of the stone while in circular motion?
*February 22, 2013*

**Chemistry**

A sample of metallic element X, weighing 4.315g, combines with0.4810 L of Cl2 gas (at normal pressure and 20.0C) to form the metal chloride with the formula XCl. If the density of Cl2 gas under these conditions is 2.948g/L, what is the mass of chlorine? The amu of chlorine is ...
*February 18, 2013*

**Physics please help im DESPERATE **

A small steel ball bearing with a mass of 17.0 g is on a short compressed spring. When aimed vertically and suddenly released, the spring sends the bearing to a height of 1.23 m. Calculate the horizontal distance the ball would travel if the same spring were aimed 39.0 deg ...
*February 8, 2013*

**physics**

If 3000ft/3 of air crossing an evaporator coil and is cooled from 75F to 55F, what would be the volume of air,in ft/3, exiting the evaporator coil?
*February 1, 2013*

**Math**

I still need help. That didn't help me.
*January 31, 2013*

**Math**

Use fraction strips to find each sum or difference. Simplify if possible. 2 1/3 + 1 2/3 3 5/6 + 4 3/6 4 6/10+ 5 7/10 1 1/6 + 3 5/6 2 4/9 + 6 7/9
*January 31, 2013*

**Math**

Estimate each sum and difference. 3 1/4 + 2 5/6 5 6/9 - 1 3/4 5 5/13 + 8 3/5 11 - 6 3/7 + 2 2/5
*January 30, 2013*

**Math**

Estimate each sum and difference. 3 1/4 + 2 5/6 5 6/9 - 1 3/4 5 5/13 + 8 3/5 11 - 6 3/7 + 2 2/5
*January 30, 2013*

**Algebra 2 **

How do the graphs of y=1/x and y=5/x+6 compare?
*January 30, 2013*

**Chemistry (Biochem)**

I'm given two pictures looking down the alpha helices of a coiled coil dimer of alpha-keratin. I'm asked to identify three statements out of the following that are true. My guesses are 2, 3, and 6. 1. Leu-Glu-His-Val-Cys-Lys-Ser is a likely repeat in the α helix ...
*January 27, 2013*

**physics**

If Santa were in the elevator at the North Pole - where the earth's radius is less than at the equator - he is closer to the center of the earth and would therefore weigh more.
*January 25, 2013*

**Physics**

A 50.0 g Super Ball traveling at 27.0 m/s bounces off a brick wall and rebounds at 17.0 m/s. A high-speed camera records this event. If the ball is in contact with the wall for 4.00 ms, what is the magnitude of the average acceleration of the ball during this time interval? (...
*January 24, 2013*

**Math**

How do I solve this math problem. -10+ V_=-3. 2
*January 23, 2013*

**Math**

How do I solve this math problem. -2-10a=158
*January 23, 2013*

**Math**

How do I go about solving this math problem. -172=-1-9p
*January 23, 2013*

**Math**

I have a word problem with fractions. Anna estimated that her brother Nick ate about 1/3 of an apple pie, her brother Matt ate 5/8 of the pie, and she ate about 1/4 of the pie. How might you convince Anna that her estimates do not make sense? Be sure to show every step of your...
*January 23, 2013*

**Physics**

A football is kicked 65 m. If the ball is in the air for 4.3 s, find its horizontal velocity vx. Enter m/s as unit and use g = 10. m/s2. What is its initial vertical velocity vy? Enter m/s as unit. With what initial speed was the football kicked? Enter m/s as unit.
*January 22, 2013*

**Physics**

Harry and Hermione look from their balcony to a swimming pool below that is 12.0 m from the bottom of their building. They estimate the balcony is 30.0 m high and wonder how fast they would have to jump horizontally to succeed in reaching the pool. What is your answer? Enter m...
*January 22, 2013*

**Physics**

Brittany throws a slingshot pellet directly at a target that is far enough away to take 0.190 s to reach. How far below the target does the pellet hit? Enter m as unit. How high above the target should she aim? Enter m as unit.
*January 22, 2013*

**Physics**

A car sits in the parking lot. Above is a cargo plane, flying horizontally at 61 m/s. At the exact moment the plane is 182 m directly above the car, a crate accidentally falls from its cargo doors. Relative to the car, where will the crate land? Enter m as unit and use g = 10...
*January 22, 2013*

**Physics**

Bert is standing on a ladder picking apples in his father's orchard. As he pulls each apple off the tree, he tosses it into a basket that sits on the ground 2.2 m below at a horizontal distance of 1.3 m from Bert. How fast must Bert throw the apples (horizontally) in order...
*January 22, 2013*

**Physics**

A ball rolls off the edge of a balcony at 8.0 m/s. Find its speed after 3.8 s in the air. Use g = 10. m/s2 and enter m/s as unit.
*January 22, 2013*

**Physics**

In her physics lab, Jessica rolls a 20-g marble down a ramp and off the table with a horizontal velocity of 1.10 m/s. The marble falls in a cup placed 0.44 m from the table's edge. Find the table's height. Use g = 10. m/s2. Enter m as unit.
*January 22, 2013*

**chinese grammar**

§Ú们礼»ª¦a©Ú绝¦oªºn¨D
*January 19, 2013*

**Science**

i belieeve you are working on penn foster :P if you are, you should email me and we can work together on it, im actually almost done with it. my email is rvargas @ live (dot) com. sorry, had to put it that way, cant post email addresses aparently :0
*January 14, 2013*

**Chemistry**

An aqueous solution of ethanol is 14.1M C2H5OH. The density of the solution is 0.853g/mL. What is molality of ethanol in the solution? What is mass % of ethanol in solution? I got the molality which is -21.7 ethanol, but I can't figure out how to get the mass % from the ...
*January 14, 2013*

**English**

A restrictive clause is one that A. usually occurs at the beginning of a sentence. B. limits the meaning of the word it describes. C. should be set off by commas. D. functions as an adverb.
*January 9, 2013*

**algebra**

81x^5 - 3x^2
*January 9, 2013*

**Statistics**

Which of the following statements is not true about samples that can be treated as matched pairs data? I. Data collected on these samples is analyzed by calculating the differences between paired observations and using that data in one sample tests. II. Each value in the first...
*December 18, 2012*

**Statistics**

The game of chuck-a-luck consists of rolling 3 dice. The player picks a number, 1, 2, 3, 4, 5, or 6. Winning and losing depends on the number of times the number appears on the top of each die. If the number appears once then the winnings are equal to the bet. If the number ...
*December 18, 2012*

**maths**

Find the probability of drawing a diamond card in each of the consecutive draws from a well shuffled pack of cards,if the card drawn is not replaced after the first draw
*December 14, 2012*

**math**

Thank you ,I think I chose that answer but I did erase at one time and chose 4/5.Find out soon enough ,working on GED and it has been some years.
*December 7, 2012*

**math**

1/5
*December 7, 2012*

**math**

those were my choices
*December 7, 2012*

**math**

If I have 25 balls in a bowl 10 black,5 blue ,5 green ,5 red . what is the probability of me pulling out a red? 1/5 ,4/5,2/10,1/25 etc....
*December 7, 2012*

**Physics**

A shear force of 3.1 105 N is applied to an aluminum bar of length L = 19 cm, width w = 5.2 cm, and height h = 2.3 cm as shown in the figure below. What is the shear deformation Äx?____m
*December 5, 2012*

**Steve help pleaseeeee**

square root of 5
*November 28, 2012*

**Algebra 2 help please :)**

What is a cubic polynomial function in standard form with zeros 1, –2, and 2? Use synthetic division to find P(3) for P(x) = x^4 – 6x^3 – 4x^2 – 6x – 2. Divide 3x^3 + 3x^2 + 2x – 2 by x + 3 using long division. Divide using synthetic division. &#...
*November 27, 2012*

**Algebra 2 help :)**

Any number in the form of a+-bi , where a and b are real numbers and b not equal 0 is considered a pure imaginary number. TRUE OR FALSE The minimum value is the smallest y-value of a function. T RUE OR FALSE i2 = square root of -1. TRUE OR FALSE Complex numbers can be graphed ...
*November 20, 2012*

**Algebra 2 help!!!**

What value completes the square for the expression? x2 + 14x Use the quadratic formula to solve the equation. x2 – 7x – 6 = 0 Simplify the expression. (–2i)(8i) What are the solutions? 1/2x^2 + 2x + 3 =0 I need help
*November 20, 2012*

**Algebra 2**

Can you double check my answer The lengths of the sides of a rectangular window have the ratio 1.6 to 1. The area of the window is 2,560 square inches. What are the dimensions of the window? (1 point) 50.6 inches by 50.6 inches 40 inches by 64 inches 40 inches by 80 inches <...
*November 18, 2012*

**HELP ! Algebra**

Solve the quadratic equation by completing the square. (-x^2 + 6x + 10 = 0)
*November 16, 2012*

**HELP !!! Algebra 2 **

15. What is the solution of the linear-quadratic system of equations? {y = x^2 + 5x - 3} {y - x = 2}
*November 16, 2012*

**Statistics**

@John I have come from a year later to reply to your concern, to uproot this tyranny that is Math Guru. No longer shall we sit wondering what the other half of the question is. No longer must we be given a formula and have to solve it out. NO LONGER MUST WE SIT THROUGH THIS. ...
*November 5, 2012*

**Statistics**

I got only love for John. The answer is fate
*November 5, 2012*

**physics**

Since the masses stick together, there is conservation of momentum but no conservation of energy. Let x be the new velocity. Hence, 0.5*0.4 + 0.8*(-0.20) = (0.5+0.8)*x X = (0.2-0.16)/1.3 = 0.0307 m/s KE = 0.5*1.3*0.0307^2 = 0.000615 J.
*October 30, 2012*

**Science**

While traveling along a highway a driver slows from 24 m/s to 15 m/s in 12 seconds. What is the automobile's acceleration? How would I show the work and find this answer?
*October 29, 2012*

**Algebra 2**

3. Identify the vertex and the axis of symmetry of the graph of the function y = 3(x + 2)2 – 3. (1 point) A- vertex: (2, –3); axis of symmetry: x = 2 B- vertex: (–2, –3); axis of symmetry: x = –2 C- vertex: (2, 3); axis of symmetry: x = 2 D- vertex...
*October 25, 2012*

**chemistry**

how many milliliters of 0.250 M KMnO4 are needed to react with 3.55 grams of iron(II)sulfate, FeSO4? the reaction is as follows: 10FeSO4(aq)+2KMnO4(aq)+8H2SO4(aq)¨ 5Fe2(SO4)3(aq)+2MnSO4(aq)+K2SO4(aq)+8H2O(l)
*October 23, 2012*

**chemistry**

WHAT IS THE VOLUME IN MILLILITERS OF 0.100 SULFURIC ACID CONTAINING 0.949 GRAMS H2SO4
*October 23, 2012*

**Algebra 2 Helpp :(**

QUESTIONS (vvv) (1) Solve the system by subsitution 2x + y = -11 3 - 4y = 11 (2) Solve the system by elimination 2x + 6 = -12 5x - 5y = 10 (3) What is the solution of the following system? -3x - 2y = -12 9x + 6y = -9 (4) What is the solution of the following system? x - y = 11...
*October 23, 2012*

**Algebra 2 Please Help**

22. The graph of g(x) is f(x) translated to the left 8 units and up 2 units. What is the function rule for g(x) given f(x) = x²? (2 points)
*October 22, 2012*

**Algebra 2 Please Help**

Please show your work on how you got the answer please and thank you :)
*October 22, 2012*

**Algebra 2 Please Help**

21. A candle is 17 in. tall after burning for 3 hours. After 5 hours, it is 15 in. tall. Write a linear equation to model the relationship between height h of the candle and time t. Predict how tall the candle will be after burning 8 hours. (2 points)
*October 22, 2012*

**Ratios of Similar Figures**

is number 5 c?
*October 22, 2012*

**nutrition**

Jonathan, a two-and-a-half-year-old, lives with his mother and brothers at his grandmother's house in Chicago. His mother, Anita, works at a pharmacy to support the family. Jonathan spends his days at home with his grandmother. While Anita works, his grandmother brings the...
*October 18, 2012*

**History**

ccbdb
*October 17, 2012*

**Microeconomics - University of Boston**

4. If Cassandra bought 16 cotton blouses last year when her income was $40,000 and she buys 24 cotton blouses this year when her income is $50,000, then what is her income elasticity of demand? Interpret what the income elasticity of demand you just calculated means to you. ...
*October 17, 2012*

**Microeconomics**

4a. In the market for hand-made guitars, when the price of guitars is $800, annual revenues are $640,000. When the price falls to $700, annual revenues decline to $630,000. Over this range of guitar prices, is the demand for hand-made guitars elastic, unit-elastic, or ...
*October 17, 2012*

**Microeconomics**

The producer of X is contemplating a price change and has asked for your advice. After some empirical investigation, you conclude that the price elasticity of demand for X is 1.25. As an economist, what would you advise the producer to do in order to raise total revenue? Would...
*October 17, 2012*

**Physics**

In Case A the mass of each block is 4.8 kg. In Case B the mass of block 1 (the block behind) is 9.6 kg, and the mass of block 2 is 4.8 kg. No frictional force acts on block 1 in either Case A or Case B. However, a kinetic frictional force of 9.4 N does act on block 2 in both ...
*October 14, 2012*

**chemistry**

in an experiment, 2.50g of salicylic acid is reacted with 10.31g of methanol. the yield of methyl salicylate, C8H8O3, is 1.27g. what is the percentage yield?
*October 13, 2012*

**chemistry**

if a reaction vessel contains 11.5g NH3, 12.0g O2, and 10.5g CH4, what is the maximum mass in grams of hydrogen cyanide that could be made?
*October 13, 2012*

**chemistry**

in a reaction of 3Cu(s)+ 8HNO3(aq)¨ 3Cu(NO3)2(aq) +2NO(g) + 4H2O(l). if 5.58 grams of Cu(no3)2 is made how many grams of nitrogen monoxide is present
*October 12, 2012*

**chemistry**

copper metal reacts with nitric acid. assume that the reaction is 3Cu(s) + 8HNO3(aq) ——> 3Cu(NO3)2(aq) + 2NO(g) + 4H2O(l). if 5.58 grams of Cu(NO3)2 is obtained, how many grams of nitrogen monoxide would have formed
*October 12, 2012*

**Science**

In the early 20th century, some scientists were reluctant to accept the conclusion that DNA could be the genetic material because it is so_________________.
*October 9, 2012*

**IMPERIALISM AND THE PROGRESSIVE ERA**

Ivy L. Lee
*October 9, 2012*

**Biology**

A bacterium that synthesizes an enzyme that neutralizes an environment toxin would probably use a(n) _____________ operon to regulate production of the enzyme.
*October 9, 2012*

**world history**

you should email me, im also in Penn Foster lol we could cut work in half if we work on this crap together.. rvargas1020 @ live . com
*October 6, 2012*

**english 4**

Please explain to me how to determine the answer im looking for
*October 3, 2012*

**english 4**

if i knew i would not ask
*October 3, 2012*

**english 4**

The two waiters exchanged a look whose meaning was clear to me. what type of clause or phase is used?
*October 3, 2012*

**english4**

can you explain to me how to determine what type of verbal it is my choices are Participle, Gerund, and infinitive
*October 3, 2012*

**english4**

What do you think Ms. Sue
*October 3, 2012*

**english4**

Well as the verbal i chose "to be moved" im not sure what type of verbal it is!
*October 3, 2012*

**english4**

He will not allow the table to be moved. identify the Verbal in the sentence and type of verbal
*October 3, 2012*

**english4**

what type of clause or phrase is used in the sentence: we hit a snag while rowing to shore
*October 3, 2012*

**math**

Average Growth Rate(2000-2009)of China - GDP: 10.9 Population: 0.8 Per Capita GDP: 10.1 Ethiopia - GDP: 7.5 Population: 2.8 Per Capita GDP: 4.7 How fast does total output(GDP)have to grow in order to raise per capita GDP in Instructions: Enter your responses to one decimal ...
*October 3, 2012*

**English **

What are the nouns and verbs in the sentence. Life is full of choices, so I must learn to make good ones.
*September 27, 2012*

**Biochemistry**

Acetylcholinesterase catalyzes the hydrolysis of the neurotransmitter acetylcholine: Acetylcholine + H2O actetate + choline The KM of acetylcholinesterase for its substrate acetylcholine is 9 x 10-5 M. In a reaction mixture containing 5 nanomoles/ml of ...
*September 22, 2012*

**Linear Algebra**

awesome, thanks a lot Steve, that link will come in handy!
*September 21, 2012*

**Linear Algebra**

Solve the following system using Gauss's algorithm (a) x1 + 2x2 + 4x3 + 6x4 = 3 2x1 + x2 + 3x3 = -6 -2x1 + x2 + 6x3 + 4x4 = -11 2x1 + x2 + x3 = 0 so the matrix will be: 1 2 4 6 3 2 1 3 0 -6 -2 1 6 4 -11 2 1 1 0 0
*September 21, 2012*

**Math**

Staring from the pit, Helen made three laps around a circular track at 40 seconds per lap. She than made a 30-second pit stop and two and a half laps before running off the track and getting stuck in the mud for the remainder of the race. Graph Helen's distance from the ...
*September 18, 2012*

**Calculus**

Calculate the following integral and determine whether it's convergent, or divergent. integral at [-3,0] x dx / sqr(9 - x^2)
*September 15, 2012*

**calculus**

Thanks Reiny and Steve. Now to pass the exam!
*September 14, 2012*

**calculus**

Calculate the following integral: ∫ dx / x(1 - √x)^2
*September 14, 2012*

**Calculus**

thanks Steve! You're a lifesaver
*September 13, 2012*

**Calculus**

Calculate the following integral: ∫ sec^4 (3x)/ tan^3 (3x) dx For this one, can I bring up the tan to tan^-3?
*September 13, 2012*

**Algebra**

Algebra Question: A team wins 15 of their first 20 games. If they win only half the time from now on, how many games will they have to play in order to win 60% of their total games? I have it figured out manually, but cant get it in equation form.
*September 12, 2012*