# Posts by mark

Total # Posts: 1,608

**math**

what is the value of y when x=2 in the equation y=-4x - 5?

*May 9, 2012*

**Foreign languages**

Thank you, Writeacher. I need to check a few other things. 1) Have you received the emails from my students? When will they get in touch with their parners? 2) When will you be in France? 3) As you know, we won't be able to start with the student exchange programme unless ...

*May 9, 2012*

**math**

simplify the following expression: 11!/3!8!

*May 2, 2012*

**Chemistry**

Which of the following compounds contains 57.5% sodium by mass? *NaI *NaOH *NaHCO3 *NaSO3

*April 30, 2012*

**math**

A sequence has t(sub1) = 5 and t(sub2) = 15 a. if the sequence is geometric, what is the common ratio? What do t(sub3) and t(sub4) equal? b. if the sequence is arithmetic, what is the common ratio? What do t(sub3) and t(sub4) equal?

*April 28, 2012*

**science**

The lock-and-key model holds that?

*April 26, 2012*

**Physics**

A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20C. What is the number density of the oxygen? in m^-3 What is the reading of a pressure gauge attached to the tank? in kPa

*April 25, 2012*

**physics**

a car of mass 3000kg moving at 20m/s is suddenly brought to a stop when a deer crosses the road. if a braking force of 300,000 is needed to bring the car to a stop, what was the duration of the force?

*April 24, 2012*

**English**

will have, are going to see and will get? correct or not?

*April 24, 2012*

**English**

Hello! Need some help with these 3 sentences. They have to be filled with either simple future, going to future or present continuous 1. Son: Mum, what are we having for dinner tonight? Mum: I haven’t decided yet. But I think we __________(HAVE) pasta. 2. ...

*April 24, 2012*

**math**

write the particular equation of a quartic function that could, according to Descartes Rule of Signs have four positive zeros.

*April 21, 2012*

**Physics**

Use the equation K=w/v and solve for v.

*April 13, 2012*

**physics**

Where must an object be placed to have a magniﬁcation of 3.74 in front of a converging lens of focal length 14.1 cm?

*April 11, 2012*

**Trigonometry**

Solve the equation sin^2x-cos^2x=0 over the interval [0, 2pi). Having trouble getting started.

*April 1, 2012*

**English**

Hello Any suggestions for a game? English learners (15 year olds) The class lasts for 20 minutes. They don't want anything with grammar, vocabulary and so on. They said they want to play something! Do you have something from your classroom?

*March 29, 2012*

**chemistry**

calculate the ph of 20 ml of .1M NaOH to 40 ml of acetic acid

*March 29, 2012*

**chemistry**

calculate the ph of 20 ml of .1M NaOH to 40 ml of acetic acid

*March 29, 2012*

**chemistry**

calculate the ph of 20 ml of .1M NaOH to 40 ml of acetic acid

*March 29, 2012*

**chemistry**

calculate the ph of 20 ml of .1M NaOH to 40 ml of acetic acid

*March 29, 2012*

**student**

an average length of 2 inches and a standard deviation of .005 inches. What is the 95% confidence interval for the length of these screws?

*March 26, 2012*

**science**

are you from QUT? because that question is on the assignment

*March 20, 2012*

**statistics**

7. The average length of time per week that students at this university spend on homework is normally distributed with a mean of 18 hours and a standard deviation of 3 hours. If Diane spends more time on homework each week than 75% of students, what is the minimum time she ...

*March 20, 2012*

**math**

If (x + 2) is a factor of m^2x^4 + 5mx^3 + x^2 – 7x – 2, find m. (4 marks)

*March 20, 2012*

**math**

Find the slope of the secant to the curve f(x) = -2logx + 3 between: (1 each) i) x = 1 and x = 2 ii) x = 1 and x = 1.5 iii) x = 1 and x = 1.1 vi) x = 1 and x = 1.01 b) Extend the result from part a to determine the slope of the tangent to the curve at x = 1 accurate to 3 ...

*March 19, 2012*

**math**

Determine the value of each of the following logarithmic expressions. Do not change bases. A) log8 4 <----- 8 is subscript b)log 1/3 27 <---- 1/3 is subscript

*March 19, 2012*

**Sta**

It is pretty common across most schools to find the grades at the MBA level divided between A’s and B’s. As such, you expect the mean GPA to be around 3.50. Using the sample of 200 MBA students, conduct a one-sample hypothesis test to determine if the mean graduate ...

*March 17, 2012*

**algebra**

If you purchase an item for 1,272 at an interest rate of 9.8%, and you finance it for 1 year, how much is the amount of add -on interest?(round your answer to nearest dollar.)

*March 14, 2012*

**Statistics Question (Confidence Interval)**

A sample of 15 recent college graduates found that starting salaries for attorneys in New York City had a mean of $102,342 and a standard deviation of $21,756. Construct a 95% confidence interval for the average starting salary of all attorneys in the city. A. (89869.82, ...

*March 14, 2012*

**Physics**

A particle travels 15 times around a 10-cm radius circle in 42 seconds. What is the average speed (in m/s) of the particle? = I think I use the v=(2pi*r)/T equation? Right?

*March 13, 2012*

**English - Native speakers**

so the problem is the tense or?

*March 4, 2012*

**English - Native speakers**

Question: Which 2 answers are correct? Which is not and why? 1. Sorry, I can't. I'm seeing my grandmother. 2.Sorry, I can't. I'm going to see my grandmother. 3. Sorry, I can't. I'll see my grandmother.

*March 4, 2012*

**English**

Hello How to explain to students the difference between may, might and could when it comes to possibility?

*February 28, 2012*

**Physics (IMPULSE)**

A cart traveling at 0.3 m/s collides with stationary object. After the collision, the cart rebounds in the opposite direction. The same cart again traveling at 0.3 m/s collides with a different stationary object. This time the cart is at rest after the collision. In which ...

*February 27, 2012*

**Physics**

A cart traveling at 0.3 m/s collides with stationary object. After the collision, the cart rebounds in the opposite direction. The same cart again traveling at 0.3 m/s collides with a different stationary object. This time the cart is at rest after the collision. In which ...

*February 27, 2012*

**Physics**

A 0.1-kg object is traveling to the right (in the positive direction) with a speed of 2 m/s. After a 0.2 s collision, the object is traveling to the left at 3 m/s. What is the magnitude of the impulse (in N-s) acting on the object? The answer must be positive.

*February 27, 2012*

**chemistry**

4KCl + 4HNO3 + O2 ==> 4KNO3 + 2Cl2 + 2H2O I meant from * combustion decomposition synthesis single replacement double replacement

*February 26, 2012*

**chemistry**

4KCl + 4HNO3 + O2 ==> 4KNO3 + 2Cl2 + 2H2O what kind of reaction is this?

*February 26, 2012*

**chemistry**

Potassium nitrate is made by adding potassium chloride to hydrogen nitrate in the presence of oxygen gas. Along with the potassium nitrate, chlorine and water are produced. How would write the equation?

*February 26, 2012*

**physics**

A 1.50 103-kg car starts from rest and accelerates uniformly to 18.5 m/s in 11.3 s. Assume that air resistance remains constant at 400 N during this time. (a) Find the average power developed by the engine. 1 W (b) Find the instantaneous power output of the engine at t = 11.3 ...

*February 24, 2012*

**physic**

A projectile is fired from the origin (at y = 0s m) a shown in the figure. The initial velocity components are v 0x = 940 m/s and v 0y = 96 m/s. The projectile reaches maximum height at point P, then it falls and strikes the ground at point Q. In Fig. 3.1, the y-component of ...

*February 22, 2012*

**chemistry**

what did amedeo avogadro contribute to the atomic theory?

*February 21, 2012*

**math**

Transform the following. Do not evaluate. log (3*4) log 3^4

*February 19, 2012*

**math**

and show work

*February 16, 2012*

**math**

4x-y=3 4x+y=1 sorry

*February 16, 2012*

**math**

2x+3y=3 3y=5-2x 4x-y=3 4x=y=1 solve and explain please

*February 16, 2012*

**English**

Hi! Any ideas on an activity which could last for 45 minutes? The topic - Valentine's day Learners: 16 year old, 30 in the class, learning English as a foreign language for 7 years

*February 13, 2012*

**English - Native speakers**

Please paraphrase the phrase into a bit simpler English involving arrested development of engorged stages or of eggs.

*February 10, 2012*

**American Government**

Thank you I think I know what I can put for my answer now.

*February 8, 2012*

**American Government**

What are two present day example that shows establishing justice? I'm not very good with coming up with modern examples only historical ones.

*February 8, 2012*

**Geography**

What are 5 precious resources that Africa possesses in abundance?

*February 8, 2012*

**math**

5/315

*February 8, 2012*

**Physics**

tan(theta)=0.800/0.625

*February 5, 2012*

**English**

Hello If you had a topic "Murphy s law" and you had to work on it in the classroom for 90 minutes, what would you do? I have a text on Murphy s law, I thought to teach the children time clauses. My idea: work on the text for 45 minutes and then introduce time clauses...

*February 5, 2012*

**algebra**

Simplify: 53 x 56

*February 2, 2012*

**chemistry**

a certain paint has a density of 0.914 g/mL. you need to cover a wall that is 7.6 meters long and 2.74 meters wide with a layer of paint that is 0.13 mm thick. what volume of pain (in liters and gallons)is required? what is the mass (in grams and pounds) of paint layer?

*February 1, 2012*

**math**

Find a common denominator: 5/8 + 5/6 = 15/24 + 20/24 = 35/24

*January 31, 2012*

**English**

Hello Can you please come up with a few questions on the following topic: my free time I need to have a few questions which I would answer and in that way write my essay. But I am totally out of ideas :/

*January 30, 2012*

**business**

I need help Describing the organizational structure for Walmart.

*January 29, 2012*

**English - Native speakers**

Hello I have a question concerning the following sentence: Teachers are these days very patient and give more information and they explain it better. Can we say explain them better also? Which one is correct?

*January 29, 2012*

**English**

I put the wrong subject sorry. Needed it in German. I'll try to find something. Thank you :)

*January 26, 2012*

**English**

Can you give me a good topic for 30 minute discussion in German language? I just want to warn you that the class is pretty lazy, unmotivated, always sleepy and uninterested. They are 18 and 19 years old and are learning German for 9 years as a foreign language, but their level...

*January 26, 2012*

**Statistics-Probability**

P(6)=(8)^6/6!e-8

*January 25, 2012*

**University of Phoenix**

I need to evaluate the planning function of management as it relates to the organization's goals and strategies. I need to use the steps in the planning process. I do not know where to begin The class in MGT/230

*January 23, 2012*

**Word 2007-pages**

Hello Does anyone know how to number the first 4 pages in a word document (2007) with roman numbers and then start from the fifth page with the number 1?

*January 23, 2012*

**chemistry**

I got C_4 H_3 O_8 for this question but I'd like someone to check my answer, please. A 1.012 g sample of a compound containing C, H, and O was burned to produce 2.145 g CO2 and 0.3293 g H2O. Calculate the empirical formula of the compound

*January 21, 2012*

**chemistry**

Is this correct? A 0.1471 g sample of a compound containing C, H, and F was burned to produce 0.1960 g CO2 and 0.08024 g H2O. If the molar mass of the compound was determined to be approximately 66.05 g/mol, what is its molecular formula? My answer is: C_12 H O_20

*January 21, 2012*

**Chemistry**

A 0.5595 g sample of a compound containing C, H, and O was burned to produce 1.429 g CO2 and 0.5850 g H2O. If the molar mass of the compound was determined to be approximately 86.13 g/mol, what is its molecular formula?

*January 20, 2012*

**chemistry**

I ended up with C_2.809 H_2.106 O_1 so would that be C_3 H_2 O?

*January 20, 2012*

**chemistry**

I need help with this problem... A 1.208 g sample of a compound containing C, H, and O was burned to produce 2.561 g CO2 and 0.3930 g H2O. Calculate the empirical formula of the compound. I always get stuck when it comes to finding the subscript for this compound.

*January 20, 2012*

**Chemistry**

A 0.5595 g sample of a compound containing C, H, and O was burned to produce 1.429 g CO2 and 0.5850 g H2O. If the molar mass of the compound was determined to be approximately 86.13 g/mol, what is its molecular formula?

*January 19, 2012*

**Math**

john's columm covered the first 12 miles in 4 hours. he then increased the speed by 2 miles per hour. if the total distance of the trip was 52 miles, how long did it take to finish the trip

*January 12, 2012*

**Algebra 1**

2(8+4c)=32

*January 12, 2012*

**math**

i need help because i have to get to bed i hae work at 3:00 in the morning i need to help my lil bro with these questions please

*January 6, 2012*

**math**

helping lil bro with homework and he forgot to bring his books home and I cant remember anything 1. The word “risk” is used often in insurance discussions. Assume you have an apartment and how likely you are to buy Renter’s Insurance? 2. When you buy auto ...

*January 6, 2012*

**BIO**

Organisms that live in environments and are hypotonic have cell membranes that differ in permeability from those that live in isotonic environments. What water regulation adaptations might have evolved to allow these organisms to survive in different environments such as the ...

*December 19, 2011*

**statistics**

Do you think there is a correlation between CEO salaries and the degree of success of a company? If you were to take a sample of companies with comparable size, market capitalization, and product category, and plot CEO salaries against the net profit of their respective ...

*December 17, 2011*

**Statistics**

6. If we reject H0:µ = 10 in favor of Ha:µ 10 at a given level of significance with a positive value of the test statistic z, then if we test H0:µ = 10 versus Ha:µ > 10 using the same sample, Ha:µ > 10 will ______ be rejected at the same ...

*December 17, 2011*

**English - Native speakers**

Need a help from a native speaker of English. Can you fill in this text by using either Past Simple, Past Continuous or Past Perfect? You would really help a lot. Thank you When Craig Myers ____bought______(buy) his restaurant, he got it for a very good price because it ...

*December 12, 2011*

**English - Native speakers**

but i have the answers. :) Can you check them? bought, had been, wanted, was, was driving, didn't believe, had bought, called, was, was, tidied, was singing, went, checked, were, didn't feel, locked, started, fell, were sitting

*December 12, 2011*

**English - Native speakers**

Need a help from a native speaker of English. Can you fill in this text by using either Past Simple, Past Continuous or Past Perfect? You would really help a lot. Thank you When Craig Myers __________(buy) his restaurant, he got it for a very good price because it _________(be...

*December 12, 2011*

**physics**

A 69 kg person on skis is going down a hill sloped at 36° below the horizontal (+x direction). The coefficient of friction between the skis and the snow is 0.15. Find the x and y components of the weight of the skier going downhill.

*December 11, 2011*

**biology**

6) If the DNA sequence is GTAC, what will be the mRNA sequence? a) CATG b) CTUT c) CAUG d) UCGG 7) Given the codon UGC, what will be its anticodon? a) ACG b) TCG c) TGC d) AAT

*December 6, 2011*

**Physics**

Trailing by two points, and with only 1.00 s remaining in a basketball game, a player makes a jump-shot at an angle of 35.0o with the horizontal, giving the ball a velocity of 8.50 m/s. The ball is released 0.25 m below the height of the basket, which is 3.05 m above the floor...

*December 4, 2011*

**Human Resource**

Compare and contrast the following methods of job evaluation and include examples that are not the same as in the textbook to demonstrate understanding: Lott, Benge, and Multiple Regression. Identify the key differences.

*November 27, 2011*

**English-tenses**

thank you :) much clearer now ;)

*November 25, 2011*

**English-tenses**

Hello I have key answers for the following tasks but I would like a native speaker to explain to me the uses of tenses here.The students have to put past tenses here. I am especially confused with the sentence beginning with The vases, which.... isn't it a rule when we see...

*November 25, 2011*

**statistic**

based on 125 flights, 76% arrive on time. whats the probability that 80 flights arrive on time, probability that 20 or less flights are late?

*November 23, 2011*

**math**

Determine the least possible value for B to the nearest tenth if A = 30°, a = 5, and b = 8.

*November 23, 2011*

**managerial economics**

Recently one of the nation’s largest consumer electronics retailers began a nationwide television advertising campaign kicking off its “Take It Home Today” program, which is designed to encourage electronics consumers to buy today rather than continue postponing...

*November 15, 2011*

**managerial economics**

draw a game tree when sony makes its technology decision first.does sony experience a first-mover advantage

*November 15, 2011*

**Trig**

Thanks. Makes sense. My problem was I was trying to use another double argument property.

*November 14, 2011*

**Trig**

Solve the equation in the given domain cos 4x + cos 2x = 0, 0<(or equal to) x < pi

*November 14, 2011*

**physics**

A bullet of mass 4.7 g is fired horizontally into a 2.4 kg wooden block at rest on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.28. The bullet stops in the block, which slides straight ahead for 2.2 m (without rotation). (a) What is ...

*November 8, 2011*

**Science**

A 110.0 kg box is pushed by a horizontal force F at constant speed up a frictionless ramp which makes an angle of 35.0 deg with the horizontal. Find the magnitude of the applied force F.

*October 26, 2011*

**Science**

A lamp is suspended by a massless string from the ceiling of a descending elevator which decelerates at 1.6 m/s2. If the tension in the string is 82.0 N, what is the mass of the lamp?

*October 25, 2011*

**Chemistry**

The Ka of a monoprotic weak acid is 2.04 × 10-3. What is the percent ionization of a 0.181 M solution of this acid?

*October 25, 2011*

**physics**

The bead is accelerating on the horizontal plane in a circle with radius r=RsinB. This is derived from the angle that the bead makes with the vertical. Once you have the radius of the particles trajectory you need to find the forces acting on it. The two forces acting on the ...

*October 24, 2011*

**Physics**

A mortar shell is launched with a velocity of 100m/s at an angle of 30 degree above the horizontal from a point on a cliff 50m above a level plain below. How far from the base of the cliff does the mortar shell strike the ground?

*October 24, 2011*

**statistic**

A survey was made of 100 customers in a department store. 70 of the customers indicated they visited the store because of a newspaper advertisement. The remainder had not seen the ad. A total of 40 customers made purchases; of these customers, 30 had seen the ad. What is the ...

*October 24, 2011*

**statistic**

Wendy is a randomly chosen member of a large female population, in which 13% are pregnant. Wendy tests positive in a pregnancy test. Pregnancy test correctly identifies pregnancy 91% of the time and correctly identifies non pregnancy 95% of the time. What is the probability ...

*October 24, 2011*