Sunday

April 26, 2015

April 26, 2015

Total # Posts: 2,204

**math**

asdf
*April 22, 2013*

**Chemistry**

What [PB2+] should be maintained in Pb(NO3) to produce solubility of 1.0*10^-4 mol PbI2/L when PbI2 (s) is added? Ksp for PbI2 is 7.1*10^-9 I can't figure it out...
*April 21, 2013*

**Science-Chemistry**

Methyl amine is a weak base with a pKb=3.35. Consider the titration of 30.0mL of .030M of Methyl amine with 0.025M HCl. a) Write the appropriate equation for the reaction. b) Calculate K for the reaction in part (a). c) Calculate pH of the initial methyl amine solution (0mL ...
*April 19, 2013*

**Physics**

A singly charged positive ion has a mass of 2.74 10-26 kg. After being accelerated through a potential difference of 268 V, the ion enters a magnetic field of 0.450 T, in a direction perpendicular to the field. Calculate the radius of the ion's path in the field. cm
*April 17, 2013*

**Math**

Remy can chop 5 carrots in 3 minutes. How long will it take him to chop 120 carrots?
*April 16, 2013*

**Algebra**

simplify and write in standard form (2p^2-p)+(7p^4+P^3+2p)
*April 15, 2013*

**Chemistry**

What volume of H2(g), stored at 26°C at a pressure of 141 atm, would be needed to run an electric motor drawing a current of 8.4 A for 4.8 h?
*April 14, 2013*

**math**

Marty walks to school 4 days each week. The walk talks 15 minutes. How much time does it take marty to walk to school & home each week. Is this correct? 15×4=60 it takes him an hour each week
*April 14, 2013*

**Physics**

An object that is 32 cm in front of a convex mirror has an image located 17 cm behind the mirror. How far behind the mirror is the image located when the object is 24 cm in front of the mirror?
*April 11, 2013*

**Physics**

An object is placed in front of a convex mirror with radius of curvature = 17 cm. The object's height is 3.5 cm and it is initially 25 cm in front of the mirror. Find the (a) location and (b) height of the image. Next the object moves closer to the mirror, so the object ...
*April 11, 2013*

**Math**

Kurt cut pizzas into wedges measuring 40 degrees. If each person eats one piece of pizza How many people could he feed with 2 pizzas
*April 10, 2013*

**General Chemistry II**

Also, not sure if I did this correctly: Compute the solubility in moles/ liter for each sample titrated. 2.3 g KHTar in water. 2.3/18= .128 S= (.128/0.05)= 2.56 moles/ liter Is this correct?
*April 10, 2013*

**General Chemistry II**

Why is the Ksp value larger for NaNO3 and KNO3 than water?
*April 10, 2013*

**SS Please check answers**

your not helping at all
*April 8, 2013*

**Mathematics**

System 5x+8y+6z=14 2x+5y+z=12 -3x+6y-12z=20
*April 8, 2013*

**Math**

pie chart
*April 5, 2013*

**chemistry**

3.61*10^-9
*April 4, 2013*

**geometry**

In the diagram, circle A is tangent to circle C, and segment BE is tangent to circle A. The radius of circle A is 11 meters and the radius of circle C is 8 meters. Find the area of triangle ABE to the nearest square meter.
*April 4, 2013*

**math**

What is the value of t in the solution to this systems of linear equations? 2s – 3t = –1 3s – 4t = 0 a)–5 b)3 c)-7/3 d)4
*April 3, 2013*

**math**

i got 8s-12t=-1 and 9s-12t=0 i don't get how you subtract this?
*April 2, 2013*

**math**

how do you subtract this?
*April 2, 2013*

**math**

What is the value of u in the following system of linear equations? 4u + 3v = –1 3u + 2v = 1 a) 5 b)-11/2 C)-7 d)19/3
*April 2, 2013*

**math**

Look at the revenue for videos rented (v) on a given day at two different video rental stores below r = 2v + 10 r = 1.6v + 18 After how many video rentals will the revenues of both stores be equal? a)25 b)45 c)70 d)20
*April 2, 2013*

**Chemistry**

Na2SO4 solution is slowly added to a solution which contains .10 M Ba (2+) and .1 M Pb(2+). which of the following statements descrives the result of the addition of Na2SO4
*April 1, 2013*

**Math**

the perimeter of a rectangular field is 140m. If the length is increased by 15m and breadth is decrease by 5m, the length will become 3 times the breadth. Find the length of breadth of the field.
*March 28, 2013*

**math**

the ages of a son and father are in the ratio 3:8. if the son is 35 years younger than his father. find their ages.
*March 28, 2013*

**Chemistry**

you're the best! thank you!!
*March 24, 2013*

**Chemistry**

The Ka of a monoprotic weak acid is 8.11 x 10 ^ -3. What is the percent ionization of a 0.125M solution of this acid?
*March 24, 2013*

**Chemistry**

Assuming complete dissociation, what is the pH of a 2.55 mg/L Ba(OH)2 solution?
*March 23, 2013*

**Language Arts**

Or C
*March 19, 2013*

**Language Arts**

Oh OK I was asking it for homework help and it was an abcd question. I'm thinking it might be D then
*March 19, 2013*

**Language Arts**

Help Ms. Sue! Please check if I'm correct on this question. * Which of the sentences below is the best option for a thesis statement? A.) An after-school program at the community center might involve classes, sports, and other activities in which children can take part. B...
*March 19, 2013*

**Physics**

A 50.0-kg box is resting on a horizontal floor. A force of 250 N directed at an angle of 20.7° below the horizontal is applied to the box. The coefficient of kinetic friction between the box and the surface is 0.300. What is the acceleration of the box?
*March 19, 2013*

**Science (physics)**

A particle P is launched from a point O with an initial velocity of 60m/s at an angle of 30 degrees to the horizontal. At the same time, a second particle Q is projected in the opposite direction with initial speed of 50m/s from a point level with point O and 100m from O. You ...
*March 18, 2013*

**Algebra**

3 real numbers that form a geometric progression have sum equal to 175 and product equal to 17576. What is the sum of the largest and smallest numbers?
*March 18, 2013*

**Trigonometry**

I think I did use the sine law but I am just not sure how to get a+b?
*March 18, 2013*

**Trigonometry**

I calculated it and a got a totally different answer
*March 18, 2013*

**Trigonometry**

Let N be a 5-digit palindrome. The probability that N is divisible by 4 can be expressed as \frac{a}{b}, where a and b are coprime positive integers. What is the value of a+b?
*March 18, 2013*

**Chemistry**

I keep getting 5.17 pH. but thats wrong. do I use the equilibrium values to plug into the equation?
*March 18, 2013*

**Chemistry**

Calculate the pH at the equivalence point for the titration of 0.130M methalamine (CH3NH2) with 0.13M Hcl. The Kb of methyl amine is 5.0x10-4.
*March 18, 2013*

**Education**

1. in a study examining preschoolers' responses to their peers distress, researchers used ___ to record each instance in which a child cried, followed by other children's reactions. a. time sampling b. systematic collection c. event sampling d. structured observation 2...
*March 14, 2013*

**Math**

If someone is attached to a 20 ft rope, which is attached to the corner of a building, how far can they move? If the bulding is 22 ft X 15 ft?
*March 14, 2013*

**inequality**

find the solution to the following inequality 2(2x-6)>x+3, then graph the solution.
*March 14, 2013*

**College Chemistry**

A temperature of 20o C is equivalent to approximately
*March 13, 2013*

**Math**

A field trip costs $8.50 per student. If 125 students are going on the trip and a total of $1011.50 has already been collected, how many students have not paid yet?
*March 12, 2013*

**chemistry**

it's octahedral: (ep) F - - F As F - - F Cl
*March 12, 2013*

**chemistry**

it is lower
*March 12, 2013*

**calculus**

Suppose f satisfies the differential equation dy/dx=y+1 and f(0)=1. In other words, f′(x)=f(x)+1 and f(0)=1. Use Euler's method with a step size of 0.5 to approximate f(1.5).
*March 12, 2013*

**calculus**

Consider the interval I=[6,7.6]. Break I into four subintervals of length 0.4, namely the four subintervals [6,6.4],[6.4,6.8],[6.8,7.2],[7.2,7.6]. Suppose that f(6)=19, f′(6)=0, f′(6.4)=−0.5, f′(6.8)=−0.1, and f′(7.2)=−0.1. What is the...
*March 12, 2013*

**Calculus**

Consider the ellipse plotted by x^2+9y^2=9. Find the y-coordinate of the point on the ellipse that is farthest from the point (0,1). Your answer should be expressed as a fraction of whole numbers.
*March 12, 2013*

**math**

A 2 feet piece of wire is cut into two pieces and once piece is bent into a square and the other is bent into an equilateral triangle. How much wire should be used for the square to ensure that the total area enclosed by both shapes is minimized?
*March 12, 2013*

**Math**

Write the following number in standard form (4X10 4th power)+(3X10 3rd power)+(2X10 2nd power)+(5X1)=
*March 5, 2013*

**Chemistry**

in an experiment, ammonia gas, NH3(g) was bubbled through distilled water. Some of the dissolved ammonia gas, NH3, reacted with the water to form the aqueous ammonia ions, NH4. When red litmus paper was placed in contact with the aqueous solution, the paper turned blue. This ...
*March 4, 2013*

**Physics**

Find the electric field between the plates of a capacitor given the following: (1) C= 10pF (2) the capacitor is connected to a 25 V battery (3) there is a vacuum between the capacitor plates (4) plate separation is 2 mm
*March 3, 2013*

**calculus**

F(x)= ln((3x+6)^4 (x^3 -2)^5 ) F'(x)=
*February 28, 2013*

**Language Arts**

I took the quiz and it the answer is "Bleach is a poison"
*February 28, 2013*

**Philosophy**

First, translate the following statement pair into the symbols of propositional logic (use the letters P and R) (a) We will have a picnic unless it happens to rain (b) We won’t have a picnic only if it happens to rain Second, use truth tables to classify the above ...
*February 28, 2013*

**chemistry**

Calculate the theoretical yield (g) of precipitate formed when 10.0 mL of 0.50 M magnesium nitrate is added to 5.0 mL of 0.50 M potassium phosphate? [You must first write the balanced chemical equation.] Which reactant is present in excess?
*February 26, 2013*

**Algebra**

Ellen is 11 years older than Maja. Last year Ellen was twice as old as Maja. How old is Maja now?
*February 25, 2013*

**Physics**

A child throws a ball with an initial speed of 8.00 m/s at an angle of 40.0° above the horizontal. The ball leaves her hand 1.00 m above the ground. What is the magnitude of the ball's velocity just before it hits the ground?
*February 24, 2013*

**Chemistry**

The \rm p \it K_{\rm a} of this reaction is 4.2. In a 0.74\it M solution of benzoic acid, what percentage of the molecules are ionized?
*February 21, 2013*

**geometry**

in triangle lmn altitude lk is 12cm long through point j of lk is a line drawn parallel to ms, dividing the triangle into two region with equal areas find lj
*February 20, 2013*

**Chemistry**

1) Frank and Oswalt report a molar absorptivity of 4700 L mol^-1 cm^-1 for thiocyanatoiron(lll) ion. What absorbance would you expect for a soloution that it 1.0e-4 M in thiocyanatorion(lll) ion, if the path length is 1.00 cm? 2) At a given temperature, the equilibrium ...
*February 19, 2013*

**Chemistry **

2 SO2 (g)+O2 (g)→2 SO3↑ How many grams of SO3(g) are formed if 8.45 grams of oxygen are used?
*February 18, 2013*

**programming**

I need to figure this problem out, I am using visual studio C#. • Powers - Write an application that displays a tables of squares and cubes of an integer from 1 to an upper limit. The user should enter the upper limit and press the calculate button. The application should...
*February 17, 2013*

**Physics 2 with calculus**

The wires leading to and from a 0.12--diameter lightbulb filament are 1.5 in diameter. The wire to the filament carries a current with a current density of 4.0×105 . what is the current density in the filament?
*February 15, 2013*

**Math**

Write the word form for 450, 708 Is it four hundred and fifty thousand, seven hundred and eight
*February 14, 2013*

**physics**

A 50.0-kg box is sliding on a rough horizontal floor, and the only horizontal force acting on it is friction. You observe that at one instant the box is sliding to the right at 1.5 m/s and that it stops in 2.5 s with uniform acceleration. What magnitude force does friction ...
*February 14, 2013*

**Trig/precalc**

Cos[x + (7 Pi)/4] + Cos[x - (7 Pi)/4] = 1
*February 12, 2013*

**Calculus**

ok thank you
*February 11, 2013*

**Calculus**

Find the derivatives of the function k(x)=sqrt(sin(2x))^3 I think I have the answer and was wondering if i had it correct k'(x)=2sin(x)^3+8sin(x)
*February 11, 2013*

**calculus**

Find the derivatives of the functions k(x)=(x^3+e^x)^4
*February 11, 2013*

**Spanish**

Translate: I have a big nose. Is it: Tengo la nariz grande. or : Tengo una nariz grande. My teacher says you must use el, la, los, and las with body parts.
*February 10, 2013*

**physics**

A golfer hits a shot to a green that is elevated 3.00 m above the point where the ball is struck. The ball leaves the club at a speed of 16.1 m/s at an angle of 52.0¢ª above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air...
*February 8, 2013*

**math-trig**

tan(t)-sec^2(t)/tan(t)
*February 8, 2013*

**Languege arts**

Nice job helper i needed help with that and u got them all right thanks! :)
*February 7, 2013*

**math**

13 2/9 - 8 8/9
*February 7, 2013*

**math**

13 2/9 - 8 8/9
*February 5, 2013*

**math**

Hello. I am having a little bit of touble with algebra, distributive property. The question is -20 (19-a) can you please help?! Thanks!
*February 4, 2013*

**Spanish**

I need to decide if these capitalized words are preterite or imperfect and I just don't get it. Could someone help me out please? Here is the story: I need help with this story. Could you please tell me if the words that are in all CAPITAL letters are preterite or ...
*February 4, 2013*

**algebra**

determine the given quadratic function has a minimum valueor maximum vale. Then find the coordinates of the minimum or maximum point. f(x)=x^2=2x-9
*February 4, 2013*

**Intro to Computer Engineering**

When solving 5x^2-50x+125=0, a space alien got x=8 for one of the two roots. What possible base could the alien be using? (Note: the coefficients are also in this base. That is 5,50,125 are all in this mystery base as well)
*January 31, 2013*

**Chemistry**

The program still states this is incorrect
*January 30, 2013*

**Chemistry**

You carry out an exothermic reaction inside a Styrofoam cup calorimeter, using a temperature probe to monitor the temperature throughout the reaction. You find that the temperature increases 7.40 °C during the reaction. The specific heat of the reaction solution is known ...
*January 30, 2013*

**math**

write the hidden question or questions in the problem Billy Bob wins $500 in a school raffle. He decides to keep $120 for himself, give $60 to charity, and divide the rest equally among his 5 brothers & sisters. How much will each brother zor sister Recieve from billy bob?
*January 28, 2013*

**Biology**

In a population of jaguars, a gene with two alleles encodes the fur color. Allele B causes melanism (dark fur) and is dominant over allele b, which results in light colored fur. Suppose that there is a migration event, producing a population with 60% BB, 20% Bb and 20% bb ...
*January 28, 2013*

**Pre calc**

Please finish y+7=6/7x-30/7
*January 25, 2013*

**Physics**

a) If the lizard has a specific heat of 4.2 J/(g x C), what is rate of increase of the lizard’s temperature? (b) Assuming that there is no heat loss by the lizard (to simplify), how long must the lizard lie in the sunlight in order to raise its temperature by 5.0 C?
*January 19, 2013*

**Physics**

A lizard of mass 3.0 g is warming itself in the bright sunlight. It casts a shadow of 1.6 cm^2 on a piece of paper help perpendicularly to the Sun’s rays. The intensity of sunlight at the Earth is 1.4 x 10^3 W/m^2, but only half of this energy penetrates the atmosphere ...
*January 19, 2013*

**Physics**

A 20 g lead bullet leaves a rifle at a temperature of 47 degrees celcieus and travels at a velocity of 500 m/s until it hits a large block of ice at 0 degrees celcuis and comes to rest within it. How much ice will melt?
*January 19, 2013*

**Chemistry**

if the H+ in acid mine drainage is 6.3 x 10^-5 mol/L, the pH of the drainage water is ___. It would require ___ gal of 0.1 M Ca(OH)2 (2 is a subscrip) to neutralize the proton acidity in 1000 gal of such drainage water.
*January 19, 2013*

**Mechanics....Urgent!!**

Find the magnitude and direction of the equilibrant of two forces, one being horizontal pull of 18 N and the other a pull of 23 N at 50 degrees to the 12 N force.
*January 16, 2013*

**Mechanics & hydromechanics**

Find the magnitude and direction of the equilibrant of two forces, one being horizontal pull of 18 N and the other a pull of 23 N at 50 degrees to the 12 N force.
*January 16, 2013*

**Mechanics & hydromechanics**

Three forces pulling on a body are in equilibrium. The direction of one is due south, the direction of another is 80 degrees east of north, and the third force acts in the direction of 35 degrees west of north. If the magnitude of southerly force is 38 N, find the magnitudes ...
*January 16, 2013*

**Mechanics & hydromechanics**

A uniform 98 N pipe is used as a lever. Where the fulcrum must be placed if a 504 N weight at one end is to balance a 192 N weight at the other end?
*January 16, 2013*

**Mechanics & hydromechanics**

A uniform plank AB of length 4.6 m and weight 508 N is suspended by a vertical rope at each end.A girl of weight 305 N stands in the position 1.6 m from one end.Calculate the tension in the rope at one end using the other end as axis of rotation.
*January 16, 2013*

**Mechanics & hydromechanics**

Where a 1208 N weight must be hung on a uniform 214 m pole so that a boy at one end supports one-third as much as a man at the other end.
*January 16, 2013*