Sunday

October 23, 2016
Total # Posts: 654

**Chemistry **

A sample of cobalt, A, with a mass of 5g is initially at 25 degrees Celsius. When this sample gains 6.70J of heat, the temperature rises to 27.9 degrees Celsius. Another sample of cobalt B with a mass of 7 g is initially at 25 degrees Celsius. If sample B gains 5 J of heat, ...

*October 17, 2016*

**social studies **

Mrs. Sue I need your help. Which statement BEST describes the power of government provided by the Articles of Confederation? A) The national government held most of the power. B) Congress enforced its power by taxing the states. C) The states had more power than the national ...

*October 12, 2016*

**Math**

All the odd numbers from 51 to 5001 are written. What is the total number of digits used?

*October 4, 2016*

**math probability**

Assume that every time you buy an item of the Hong Kong Disney series, you receive one of the four types of cards, each with a cartoon character Mickey, Minnie, Donald and Daisy with an equal probability. Over a period of time, you buy 6 items of the series. What is the ...

*September 27, 2016*

**Algebra **

A rock is thrown upward with a velocity of 21 meters per second from the top of a 48 meter high cliff, and it misses the cliff on the way back down. When will the rock be 7 meters from the water, below? Round your answer to two decimal places.

*September 21, 2016*

**9th Grade Biology**

A

*September 6, 2016*

**Health**

I thick c

*September 6, 2016*

**Math**

Find the area of each triangle with the given dimensions Base=3 centimeter, height =3centimeter

*June 28, 2016*

**Ecology**

an endemic species is best defined as a species that

*June 5, 2016*

**Physics**

A charge of -5.02 μC is traveling at a speed of 8.86 × 106 m/s in a region of space where there is a magnetic field. The angle between the velocity of the charge and the field is 54.6o. A force of magnitude7.85 × 10-3 N acts on the charge. What is the ...

*May 17, 2016*

**Chemistry**

What is the molar mass of toluene if 0.85 g of toluene depresses the freezing point of 100 g of benzene by 0.47 degrees celsius? Kf= 5.12 C/m

*May 6, 2016*

**math**

A crowd of people is watching a live TV show in an auditorium. Section B of the auditorium has eight rows of seats. Each row has 10 seats. If 75 percent of Section B is occupied, how many people are seated in that section?

*April 25, 2016*

**Chemistry**

At 350 K, Kc = 0.142 for the reaction 2 BrCl(g) ⇀↽ Br2(g) + Cl2(g) An equilibrium mixture at this temperature contains equal concentrations of bromine and chlorine, 0.077 mol/L. What is the equilibrium concentration of BrCl?

*April 23, 2016*

**Physics**

Bob (80 kg) lands with a resultant GRF of 1200 N at an angle of 80 degrees from the horizontal. What was his vertical acceleration during landing? If his vertical velocity at initial contact of landing is 3.0 m/s, how much work is required to bring his body to a complete stop...

*March 20, 2016*

**Physics**

Bob (80 kg) lands with a resultant GRF of 1200 N at an angle of 80 degrees from the horizontal. Round answers to nearest whole number. What was his vertical acceleration during landing?

*March 20, 2016*

**Functions, graphs**

f(x)=(x+1)/(1+x^2) a) explain why the graph lies above the x axis on the interval x=0 and x=sqrt(3) b)write an expression using the indefinite integral that gives the area between the graph f and the x axis between the values x=0 and x=sqrt(3). c)use integration to find the ...

*March 5, 2016*

**Maxima, Stationary Points**

Thanks Reiny, Ive had a look on wolfram alpha and seen the solutions. My problem is I need to show it using Maxima but for some reason Maxima will not solve my equation 9x^6 + 28x^4 + 51x^2 - 88x - 10 = 0. So frustrating.

*March 5, 2016*

**Math Algebra**

Learning Center would like a possible net profit of $650,000 on its new resource manual it sells to schools. The fixed costs for producing the manual are $780,000 and the variable cost per package is $19.85. If the estimated unit sales are 1,250,000 units, what selling price ...

*February 26, 2016*

**algebra**

The formula will be A=P(1+r/n)^nt P stands for the initial amount invested, so P= 4000 R is the rate (.04), and N is the amount of times it is compounded per year (1). For example, saying "compounded quarterly" would make n=4. T is, of course, time (3). This makes ...

*February 25, 2016*

**Physics**

A spherical satellite has 12 identical monopropellant thrust chambers for attitude control with the following performance characteristics: thrust (each unit): 5 lbf; Is (steady state or more than 2 sec): 240 sec; Is (pulsing duration 20 msec): 150 sec; Is (pulsing duration 100...

*February 19, 2016*

**Math question/help please!**

Jacklynn draws two adjacent angles that form a right triangle. One angle measures 32°. What is the measure of the other angle?

*February 16, 2016*

**Physics**

(Someone please help me !! I don't understand this.) Two tiny conducting spheres are identical and carry charges of -27.3C and +61.0C. They are separated by a distance of 2.64 cm. (a) What is the magnitude of the force that each sphere experiences? (b) The spheres are ...

*February 9, 2016*

**math**

Chelsea has 10 yards of yarn. How many bows can be made if each bow uses 2/3 yard of yarn? Draw a diagram that represents the situation. How many 2/3 yard did he cut? Does he have any left over? How much? Write a division sentence to show the situation.

*February 3, 2016*

**chem**

The temperature of a 80.0 g sample of mate- rial increases from 15.0◦C to 42.0◦C when it absorbs 4.00 kJ of energy as heat. What is the specific heat of this material? Answer in units of J/g · K.

*February 1, 2016*

**science**

False

*January 20, 2016*

**History,Business Studies,Maths Lit,Cat,English,Afrikaans**

What can I study after Grade 12

*December 30, 2015*

**English**

I have to do a 10-minute speech based on this: Give an account of Britain’s colonial policies concerning Africa, Australia, India, and New Zealand in the 19th century. I have little to no prior knowledge of this, so I'm not really sure where to start, or what I can ...

*December 10, 2015*

**Algebra**

If x varies directly as y and x=9 when y=2 find x when y is 6

*November 24, 2015*

**geography**

Where did the Cold War take place?Please just be specific(answer in countries).

*November 16, 2015*

**math**

Least to greatest quart gallon liter pint cup deciliter

*November 9, 2015*

**Programming**

Create and test a Visual Basic application to allow teachers to enter student results. One dimension of the array will hold the results for up to 10 students. The other dimension will hold up to 5 subjects. Additionally a string based array will hold the names of the subjects...

*October 28, 2015*

**Norman**

Algebra 2 The difference of two numbers is 4. Three times the smaller minus the larger is 10. Find the numbers.

*September 30, 2015*

**science**

What is the rarest element?

*September 29, 2015*

**math**

What is the hardest expression in the world?

*September 28, 2015*

**math**

What is 57 divided by 2.95

*September 28, 2015*

**Math**

A scuba diver dives to a depth to a of 50 feet, then rises 15 feet, sinks 12 feet, then rises 20 feet, whats the answer?

*September 14, 2015*

**Math**

Suppose that a wind is blowing in the direction S45°E at a speed of 50 km/h. A pilot is steering a plane in the direction N60°E at an airspeed (speed in still air) of 150 km/h. The true course, or track, of the plane is the direction of the resultant of the velocity ...

*September 14, 2015*

**Algebra 1**

Find the range of f(x)=-x+4 for the domain {-3,-2,-1,1} A) {7, 6, 5, 3} B) {7, 6, 5, 4} C) {-7,-6,-5,3} D) {-7,-6,-5,4}

*June 30, 2015*

**governmnt**

Congress convenues every two years on_____of every____ year.

*May 8, 2015*

**Pre-calc**

There exist constants a, b, c, and d such that(sin x)^7 = asin 7x + bsin 5x + csin 3x + dsin x for all angles x. Find d. I tried rewriting them in the exponential form, but it becomes ugly as there are many negative cosines and divisions of i. Help?

*April 7, 2015*

**Physics**

A skateboarder approaches the circular hill with a velocity of 8.0 m/s at point B. The angle formed between the lines that join point AO and BO is 20 degrees. a) what is her speed at the top of the hill(Point A) if she coasts up to this point? b) what min speed must she have ...

*April 7, 2015*

**chemistry**

why doesnt the radius ratio rule work for TlCl3??? the division would be the radius of the cation / radius of the anion. For Tl3+ and Cl-...88pm/181pm = .49 which would correspond to a 'zinc blende' crystal structure and not a CsCl type crystal as the rest of the ...

*March 7, 2015*

**science**

I would say it is 0 because work is the a function of Force and horizontal displacement.

*March 7, 2015*

**Art 7**

Number 3 is D and Number 7 is D

*March 6, 2015*

**math**

A cyclist covers his outward journey downhill at 24mph. His return journey, over exactly the same distance uphill, is covered at only 12mph. What is the cyclist's average speed over the entire journey?

*March 5, 2015*

**Chemistry Help**

How many moles of H2 and N2 can be formed by the decomposition of 0.250 mol of ammonia, NH3? Is it 0.250*3mol H2=0.75 0.25*1mol N2=0.25 Am I correct?

*February 28, 2015*

**Chemistry Help**

oh i got it... thank you so much

*February 27, 2015*

**Chemistry Help**

so i have to do 1/2*0.00759=0.003795 = 3.795 mL is the answer?

*February 27, 2015*

**Chemistry Help**

Ba(OH)2 is 1/2 How can you get 1/2 from.

*February 27, 2015*

**Chemistry Help**

I still have problem on how can you get mols Ba(OH)2 from. Can you explain please

*February 27, 2015*

**Chemistry Help**

How many milliliters of 0.534 M Ba(OH)2 solution are needed to completely neutralize 34.5 mL of 0.220 M HBr solution? The reaction is Ba(OH)2(aq) + 2HBr(aq) → BaBr2(aq) + 2H2O(l) I did 0.0345 * 0.220 = 0.00759 Moles of HCl =2*0.00759= 0.01518 0.01518*1000= 15.18 mL ...

*February 27, 2015*

**Chemistry Need Help**

Thanks both of your replied. I got it now :)

*February 27, 2015*

**Chemistry Need Help**

Sorry but I still don't understand your explaining. Can you explain more briefly please. Thanks.

*February 27, 2015*

**Chemistry Need Help**

Cl2 + F2 -> 2ClF

*February 27, 2015*

**Chemistry Need Help**

Given the chemical equation, Cl2 + F2 2ClF, how many moles of ClF are produced in the reaction, if 1.50 moles Cl2 are made to react with 1.75 moles F2 ? I got the answer 3.50 moles but it was wrong. Can anyone help me please.

*February 27, 2015*

**Math**

1 inch = 15 miles: Franklin to Washington is 45 Miles (3 inches) Franklin to Lincoln is 30 miles (2 inches) How much farther from Franklin is Washington than is Lincoln? I worked it out to be 7 1/2 miles but my teacher says I am wrong? She says the answer is either 11 - 17 - ...

*February 25, 2015*

**science**

two small spheres lie 1.5 meters apart and carry identical charges. How large is the charge on each if a sphere experiences a force of 2.0 N.

*February 24, 2015*

**Math**

47. For science class, Kyle needs to make a dilute solution of 12 ounces that is 30% vinegar. But he only has 20% vinegar 60^ vinegar. How many ounces of 20% vinegar should he use? A. 3 ounces B. 6 ounces C. 9 ounces D. 10 ounces

*February 18, 2015*

**Math**

In triangle ABC, the degree measure of angle A is 20 degree greater than the degree measure of angle B. Angle C is a right angle. What is the measure of angle B? Is it 70 degrees. 90-20=70

*January 28, 2015*

**Calculus**

Ohhhhhhhhh THANKS

*January 12, 2015*

**Calculus **

F(x) = 3/4x^4 –x^3 -3x^2 + 6x Determine the interval(s) where f(x) is increasing (if any) and the interval(s) where f(x) is decreasing (if any). How do I know where f(x) is increasing or decreasing?

*January 12, 2015*

**sociology**

What does "Social Space" mean when we talk about location

*January 3, 2015*

**Sociology101**

thx

*January 2, 2015*

**Sociology101**

I found out. She said APA

*January 2, 2015*

**Sociology101**

She did not tell us which writing style to use. I think MLA is the standard.

*January 2, 2015*

**Sociology101**

I have to write an essay for my Intro to Sociology class. Do I write it in MLA or APA style?

*January 2, 2015*

**Simple math**

oh, I feel you

*December 4, 2014*

**Simple math**

If Kristin buys gas at $2.69 per gallon, which includes all taxes, what percentage of the price is the state tax? What percentage is the federal tax The state tax is .8 and federal tax is .18. So would I multiply each by the total amount the gas cost?

*December 4, 2014*

**math **

Darion needs 20 pieces of string 3/8 inch in length .He cut a 4 7/8 inch piece of string into pieces that are 3/8 of a inch long each. How many more pieces of string does he need?

*November 16, 2014*

**Operations with Fractions**

Darion needs 20 pieces of string 3/8 inch in length. He cut a 4 7/8 inch piece of string into pieces that are 3/8 of an inch long each. How many more pieces of string of string does he need?

*November 15, 2014*

**Is this correct**

Anyone??

*November 11, 2014*

**Is this correct**

f(x)= 1/3x^5 + x^-2 + 3, then f'''(x) is.. I got f'''(x)= 20x^2-24x^-5

*November 11, 2014*

**math**

A florist had an equal number of red and yellow tulips. She sold 624 red tulips. Then she had 4 times as many yellow tulips as red tulips. How many tulips did she have at first. 624 X 5 ----- 3120

*October 27, 2014*

**Physics**

A 15 kg sled experiences an applied force of 5.5 N [north] and an opposing frictional force of 2.5 N [south]. If the sled starts from rest, what will be the velocity of the sled after 4.0 s?

*October 26, 2014*

**Chemistry**

What is the difference between Citric Acid C6H8O7 and H3C6H5O7? I am seeing both and don't know which is the right one. Is one a solution of citric acid? Thanks

*September 29, 2014*

**algebra**

18x+4y=-10 9x-7y=-23

*September 4, 2014*

**math**

Area of a rectangle = 221 m2; width = length = ? Should the answer be 13 or or 26

*September 2, 2014*

**Physics**

Two boys are pulling a box across a horizontal floor as shown in the figure below. vector F 1 = 50.0 N and vector F 2 = 100 N. (a) Find the resultant (or sum) force by the graphical method. (b) Find the resultant (or sum) force by the component method.

*August 25, 2014*

**Trig**

Use the given information to evaluate sin (a-b). Exact answers. No decimals. Sin a = -7/25, cot b = 8/15; neither a nor b are in quadrant III.

*May 7, 2014*

**Math**

How many roots does x to the 3rd power -2x to the 2nd power-13x-10=0 have

*April 21, 2014*

**Educational Technology**

Anonymous is wrong

*April 16, 2014*

**Chemistry**

Doing some homework, are my answers right? HCN= Polar HCOOH= Polar H2CCCH2= Nonpolar Out of the following elements: Na, H, and Au order them least to greatest in the following: Eletronegativity= Na is smallest, H is second, Au is largest Ionization Energy= Na is smallest, Au ...

*April 3, 2014*

**Statistics**

a) E(Y) = λ t = (1/16)(16) = 1 star P(X>=2) = 1 - P(X<2) = 1 - [e^-1 + (e^-1)(1)/1!] = 0.264 b) P(X≥1) = 1 - P(X=0) = 1 - e^-μ 0.95 = 1 - e^-μ e^-μ = 1 - 0.95 e^-μ = 0.05 ln(e^-μ) = ln(0.05) -μ = -3 μ = 3 Therefore (3)(16) = ...

*February 20, 2014*

**Science**

Right Answers: True A B C C B C D

*February 3, 2014*

**chemistry**

A chemist needs a HCl solution with a molarity of less than 0.400 M for an experiment. To find out if a sample of HCl solution can be used in the lab, the chemist performs a titration to neutralize 59.2 mL of the HCl with 45 mL of 0.400 M NaOH. Based on the results, will the ...

*January 31, 2014*

**statistics**

each backpack will be weighted using kilograms for most accurate measurement. using a scale, set each backpack on the scale and record its weight. ensure before weighing that the scale is zeroed out. a platform scale is the best kind for this experiment.

*January 8, 2014*

**Stats**

A random sample of size 100 is drawn from a population with a standard deviation of 10. If only 5% of the time a sample mean greater than 20 is obtained, the mean of the population is ______.

*December 13, 2013*

**Math**

Thank you for the answer now I understand. For the next question I made a mistake this is the question elli has two 8 and 1/2 pound bags of mints. She plans to put 1/12 pound at each place setting. Will she have enough mints? She has 256 guests I think that means 256 place ...

*December 11, 2013*

**math**

Ellis plans to hand out door prizes as the guest arrive she has 256 guests every 6th guest will receive a mug and for every 14 guests will receive a t shirt. Which guest will be the first to receive both mug and at shirt? Next question is elli has 8 and 1/2 pound bags of mints...

*December 11, 2013*

**Math**

Explain how to use a protractor to measure an angle.

*December 3, 2013*

**Maths**

A flat circular disc, of radius R, can be modelled as a thin disc of negligible thickness. It has a surface mass density function given by f(r,φ) = k(1 - r2/R2), where k is the surface density at the centre and r is the distance from the centre of the disc.Using area ...

*October 28, 2013*

**Computer Programming using python**

DO IT BY YOURSELF OR YOU WILL NOT LEARN! GOOD LUCK!

*October 24, 2013*

**Algebra**

What is the mean of all even integers from 123 to 987?

*October 18, 2013*

**Physics **

An unmarked police car traveling a constant 80km/h is passed by a speeder traveling 135km/h. Precisely 3.00s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 1.50m/s^2 , how much time passes before the police car ...

*October 6, 2013*

**math**

sorry not 12 mths. 3200/600 = 5.3mths

*September 29, 2013*

**math**

x - 3y = 3200 y = 600 x - 3(600) = 3200 x = 5000 x/y = 12mths

*September 29, 2013*

**maths**

An initial-value problem is given by the differential equation, f(x,y) = x + y, y(0) = 1.64 The Euler-midpoint method is used to find an approximate value to y(0.1) with a step size of h = 0.1. Then use the integrating factor method, to find the exact value of y(0.1). Hence, ...

*September 29, 2013*

**Equation **

Four times a number, increased by 25 is 13 less than 6 times the number. What is the number? 4n+25=-13-6n. ???

*September 11, 2013*

**math**

I think

*September 3, 2013*

**math**

57.5 hr

*September 3, 2013*