Friday

January 30, 2015

January 30, 2015

Total # Posts: 761

**statistics**

I am trying to figure out how the answer of 0.989 came from the following equation of correlation. 7(-5)-(25)(13) _______________________ /7(127)-(25)*/x/7(71)-(13)*
*January 23, 2015*

**Calculus**

Evaluate each telescoping sum: 1) Sum from i = 1 to 100 of (5^i - 5^(i-1)). I know that I could apply the (n(n+1))/2 summation rule to the 5^i part of the question and then plug in 100, but I am unsure what to do for the second half --> -5^(i-1)! Thank you for any help!
*January 9, 2015*

**Chemistry**

Thank you very much!!!
*January 6, 2015*

**Chemistry**

100lbs x453.6g/lbs = 45360grams 45360 grams x 1mol/18.02 g= 2517.2 moles 2517.2mol x 6.01kj/mol = 15128.4kj 45360 grams x 4.18j/g C x 100C x 1/1000 = 18960.5 45360g x 1 mol/ 18.02g x 40.6 kj/ mol = 102198kj All added equals 136287 kj 2.54E4 J /1g x #g = 136287 kj #g= 5.36 kj
*January 6, 2015*

**Chemistry**

How do I send a picture of my work here?
*January 6, 2015*

**Chemistry **

The heat of combustion of bituminous coal is 2.5 x 10^4 J/g. What quantity of coal is required to produce the energy required to convert 100. Pounds of ice at 0.0 degrees Celsius to steam at 100.0 degrees Celsius? Is the answer 5.36 about right. I'm not sure if I did it ...
*January 6, 2015*

**Physics**

An object has a volume of 4.0m^3 and weighs 40,000 Newtons. What will be its weight in water?
*January 6, 2015*

**physics**

The small piston of a hydraulic lift has a diameter of 8 cm and its large piston has a diameter of 40cm. The lift raises a load of 15,000 Newtons. A. Determine the force that must be applied to the small piston. B. Determine the pressure applied to the fluid in the lift.
*January 6, 2015*

**Chemistry**

Does an answer around 5.36563 kg sound about right? After adding q1+q2+q3 I got 136287 kj so I converted that to J and then found the #g coal to be 5.36563 kg.
*January 5, 2015*

**Chemistry **

The heat of combustion of bituminous coal is 2.5 x 10^4 J/g. What quantity of coal is required to produce the energy required to convert 100. Pounds of ice at 0.0 degrees Celsius to steam at 100.0 degrees Celsius?
*January 5, 2015*

**physics**

all i was need a formula
*January 4, 2015*

**physics**

a pendulum 3m long is displaced at an angle of 40 degrees. What will be the maximum velocity of the pendulum when it is released to oscillate?
*January 4, 2015*

**physics**

a car rolls down a ramp 4m long that has angle of incline equal to 37 degrees. If the car starts from rest, what will be its velocity at the bottom of the ramp?
*January 4, 2015*

**physics**

e. J-s
*January 4, 2015*

**Chemistry**

Are there any structural isomers of hydrocarbons from methane to decane have 3 stereogenic C atoms? (i know that there are none for decane itself, but I am wondering about the others before it.) Thanks in advance!
*December 13, 2014*

**Physics**

A roller coaster goes 40-m along a section of track sloping 10 degrees below the horizontal, followed by a 13-m section sloping upward at 6 degrees, followed by an 26-m section of level track. Find the net displacement in m.
*December 7, 2014*

**Calculus**

A sherman is in a rowboat on a lake and 3 km from shore. He wishes to reach a store 2 km down the (straight) shore. He can row at 5 km/h and run at 13 km/h. To what point down-shore should he row to get to the store as quickly as possible? 8. The cross-section of a tunnel
*December 3, 2014*

**Calculus**

For f(x)= (x+3)^2/(4x-5) find all x such that f(x) increases.
*November 22, 2014*

**CIS**

or nah
*November 21, 2014*

**Calculus - PLEASE HELP!!**

For any real number x there is a unique integer n such that n≤x<n+1, and the greatest integer function is defined as ⌊x⌋=n. Where are the critical values of the greatest integer function? Which are local maxima and which are local minima?
*November 17, 2014*

**Physics**

You have a tanker that is filled with olive oil, which total mass = 200 kg. The tanker is in the shape of a rectangular box w/vertical sides and a horizontal cross-sectional area 0.9 m^2. How deep a swimming pool do you need so that the tanker doesn't hit the bottom?
*November 16, 2014*

**geometry**

find the perimeter and area of each figure. Give your answers in simplest radical form. 1. a 30 degree-60 degree-90 degree triangle with hypotenuse length 28 centimeters
*November 10, 2014*

**math**

well a tree diagram would work better
*November 8, 2014*

**chemsitry**

How many moles of silver chromate will be produced from 146 g of silver nitrate?
*November 3, 2014*

**Science**

thank you
*October 28, 2014*

**Science**

is it one parent?
*October 28, 2014*

**Science**

Where does a clone recieve is DNA from? My guess is two parents
*October 28, 2014*

**Math**

A tree is losing its trees. Two thirds fall off in the first week, two thirds of those remaining fall off in the second week, and two thirds off those remaining fall off in the third week. Now there are 37 leaves. How many leaves did the tree have originally?
*October 25, 2014*

**Calculus**

Find an equation of the tangent line to the curve f(x) = (sins)^2 + 2tanx at x= pi/4. I worked through it and got y = 5x + 5/2 for my answer, but the answer key says that it is y - 5/2 = 5(x - pi/4). Why is the pi/4 in the answer? Thanks for any help!
*October 19, 2014*

**Physics**

A projectile is accelerated from rest at point A along a circular track of radius 2 m, as shown in Fig. 5.1. Gravity acts in the z direction. The rate at which the speed of the projectile increases as a function of time, t, is at = 2t ms-2. What is the magnitude of the ...
*October 16, 2014*

**statistics**

A box contains 19 red marbles and 19 green marbles. Sampling at random from the box five times with replacement, you have drawn a red marble all five times. What is the probability of drawing a red marble the sixth time?
*October 12, 2014*

**Physics 30**

inquiry lab determining the refractive index of a variety of materials (Snell's Law Lab): Basically this lab: We us a polar coordinate paper and a semicircular shaped containers which we switch between, which are composed of different material. We shine a narrow light ...
*October 11, 2014*

**Math**

A spherical balloon is to be deflated so that its radius decreases at a constant rate of 12 cm/min. At what rate must air be removed when the radius is 5 cm? Must be accurate to the 5th decimal place. I keep getting -3769.91118. What am I doing wrong? Please help!
*October 5, 2014*

**Chemistry**

How do I solve these problems You have 2000. g of aqueous NaOH solution. The percent by mass of the solute is 4.25%. How many grams of NaOH are in the solution? If you have 100.0 mL of a 25.0% aqueous solution of ethanol, what volumes of ethanol and water are in the solution?
*October 4, 2014*

**real analysis**

I mean prove the supremum of the set {2-1/n: n in N} is 2
*September 30, 2014*

**real analysis**

Hello. I want make sure im doing right step. Prove the supremum of the set A={2-1/n: n in natural number} is 3. My answer Proof: lets prove supA=2 Then 2 is an upper bound of A. Let S'<2, then S' is not upper bound. There exists x in A such that x> S' Then 0...
*September 30, 2014*

**algebra**

the cinema sold 600 tickets total. adults tickets were $15 and childrens tickets were $8. they made a total of $7740. how much of each ticket were sold?
*September 23, 2014*

**real analysis**

i noticed it doesn't have x in them. i dont know what to do. prove: let epsilon>0. let f(x) = pi + 3 for x∈ real number. Prove your conjecture. Whether f is continuous for all r ∈ real number. my proof; |f(x)-f(r)|=|(pi+3)-(pi+3)|<epsilon so 0<epsilon ...
*September 20, 2014*

**real analysis**

thanks @MathMate
*September 14, 2014*

**real analysis**

definiton: A set S subsect of real number, sequence {Xn} is called bounded if there is a number M such that |X|≤ M for all x ∈ S prove the sequence (-8+(n/(n+1))) is bounded. my anwser proof: Let Xn = (-8+(n/(n+1))) there exist M in real number such that |Xn| &#...
*September 14, 2014*

**math**

Show that if a radioactive substance has a half life of T, then the corresponding constant k in the exponential decay function is given by k=-ln(2)/T I'm confused about how to show that that is true.
*September 4, 2014*

**math**

how many minutes from 11:35 am till 12:50 pm?
*May 31, 2014*

**Math**

Find the quadratic polynomial whose graph goes through the points (-2,5), (0,5), and (1,11). f(x)= ______x^2+ ______x+ _______
*May 4, 2014*

**music**

ur vt9hg5gv
*May 1, 2014*

**calc**

If y^3 = 16x^2 Determine dx/dt When x= 4 and dy/dt= -1
*April 21, 2014*

**Calc**

A particle is moving along the curve y= 4 sqrt{2 x + 2}. As the particle passes through the point (1, 8), its x-coordinate increases at a rate of 5 units per second. Find the rate of change of the distance from the particle to the origin at this instant.
*April 21, 2014*

**physics**

Imagine having an 80-turn coil with radius of 5.0 cm and resistance of 30 Ù. At what rate must a perpendicular magnetic field change to produce a current of 4.0 A?
*March 30, 2014*

**physics**

A uniform magnetic field makes an angle of 30 degrees with the axis of a circular loop of 300 turns and radius of 4 cm. The magnetic field changes at a rate of 85 T/s. Determine the magnitude of the induced emf in the loop.
*March 30, 2014*

**Math**

1. Subtract k to both sides 6k - 8 - k = k - 2 -k 5k - 8 = 2 (Remember that k is basically 1k) 2. Add 8 to both sides 5k - 8 + 8 = 2 + 8 5k = 10 3. Divide 5 to both sides 5k/5 = 10/5 k = 2
*March 19, 2014*

**math**

2/5 are women There are 132 women Find the total 2/5 = 132/x 2x = 132*5 2x = 660 x = 330 Find how many men there are 1/4 = x/330 4x = 330 x = 82.5 There are about 83 men 132 + 83 + x = 330 x = 115 There are about 115 children at the circus show.
*March 19, 2014*

**Chemistry **

What is the concentration of hydronium ions in a solution that is 0.12 M HBrO(aq) and 0.160 M NaBrO(aq)?
*March 19, 2014*

**Math**

4 + 3p = 19 Subtract both sides by 4 4 - 4 + 3p = 19 - 4 You'll get 0 + 3p = 15 3p = 15 Divide both sides by 3 3p/3 = 15/3 You'll get p = 5 Hope this helps
*March 19, 2014*

**math**

Jack has 2009 unit cubes glued together to form a cuboid. He opens a packet containing 2009 stickers. He has enough stickers to stick one on each cube. How many stickers does he have left?
*March 16, 2014*

**physics**

A 6.0 Ù resistor and a 3.0 Ù resistor are connected in parallel to a 1.5 V battery of negligible internal resistance. What is the current in the 3.0 Ù resistor?
*March 6, 2014*

**physics**

A potential difference of 2.0 V is applied across a wire of cross sectional area 2.5 mm2. The current which passes through the wire is 3.2 × 10-3 A. What is the resistance of the wire?
*March 6, 2014*

**physics**

At a critical junction in a supercomputer, the current as a function of time is given as i(t) = 3t^2-2t, where i is measured in milliamps and t is measured in seconds. How much charge passes through this critical junction during the interval 0 < t < 5.00 s?
*March 6, 2014*

**English**

Is it "watch a one of a kind performance" or "watch one of a kind performance" I thought it was the first one, while someone else thought the second. Thanks!
*February 25, 2014*

**Geometry**

ABCD is a parallelogram. P is a point on AB such that AP:AB = 1:4. Q is a point on CD such that DQ:DC = 1:3. AQ and DP intersect at R. Find the ratio AR:RQ and the ratio AR:AQ. Show work.
*February 21, 2014*

**Maths**

A true/ false test is given. If a person guesses the answers, the probability that any particular question is correctly answered is 0.5. If the test contains 14 questions and 7 correct answers is a pass, what is the probability of passing the test by simply guessing?
*February 13, 2014*

**Math**

Thank You Ms. Sue. Have a Good Night
*February 11, 2014*

**Math**

Mary and Bob sold candy. Mary sold 4/5 as much candy as Bob did. If Mary sold 1/2 box how many boxes did Bob sell? I did 4/5 divided by 1/2 and was told this was wrong???? Can someone tell me what I did wrong? Thanks You
*February 11, 2014*

**math**

The profit in dollars in producing x- items of some commodity is given by the equation P = - 40 x^2 + 1000 x - 5250 . How many items should be produced to maximize the profit? What is the maximum profit?
*February 9, 2014*

**math**

the scale on a map is 1:2500, a pond on a map has a perimeter of 12cm, how far have you actually walked
*January 10, 2014*

**Physics-forces**

A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Sometimes all this weight acts on the heels of her shoes. What is the pressure under her heels? 240n/2cm^2
*January 6, 2014*

**Physics-forces**

240n/2cm^2 240n/40cm^2 A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Why are marks left on the wooden floor by the woman's shoe heels but not her shoe soles? really need help with these questions
*January 6, 2014*

**physics**

240n/2cm^2 240n/40 cm^2
*January 6, 2014*

**physics**

A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Why are marks left on the wooden floor by the woman's shoe heels but not her shoe soles?
*January 6, 2014*

**Algebra 1**

Thanks but my teacher said that the answer is y= 2x - 9
*November 3, 2013*

**Algebra 1**

Find the y-intercept of the two coordinates ( 2, -5) and ( 6, 3). Please help me with this question and please explain to me and show me how to find Each step to solving the y- intercept. Thank you 😄
*November 3, 2013*

**calculus**

(A) Consider the wave equation with c=1, l=1, u(0,t)=0, and u(l,t)=0. The initial data are: f(x)=x(1-x)2, g(x)=sin2(pi x). Find the value of the solution at x=0, t=10, and at x=1/3, t=0. Find the value of the solution at x=1/2, t=2. (B) Suppose that l=2, c=1/2. Draw the domain...
*October 22, 2013*

**science**

if 8.100 grams of C6H6 is burned and heat is produced from the burning is added to 5691 grams of water at 21 degrees celsius what is the final temp of the water? 2C6H6+15O2=12CO2+6H2O+6524kj
*October 17, 2013*

**physics**

Gnhdjkkvfu
*October 13, 2013*

**Math**

Find two numbers the exact same answer is between 6×7,381
*September 24, 2013*

**algebra**

| x | >= -8
*September 16, 2013*

**college physics**

A sprinter can reach a speed of 9.0 m/s in 1.0 s. If the sprinter’s acceleration is constant during that time, what is the sprinter’s acceleration?
*September 5, 2013*

**stats**

explain and give example for each of the following types of variables: (a) equal-interval, (b) rank-over, and (c) nominal
*September 2, 2013*

**Theology**

Do you offer homework help in Theology?
*September 2, 2013*

**Math- Probablility**

There is a woman that has a 40% chance of being in Casper recently, a 30% chance of being in Denver and a 27% chance that she has been to both. Find the probablility that she has been to Casper if she has been to Denver.
*July 29, 2013*

**Probability**

thirty animals are to be used in a medical experiment on diet deficiency: 3 male and 7 female rhesus monkeys, 6 male and 8 female dogs. If one animal is selected at random, what is the probability of getting a chimpanzee or a dog?
*July 29, 2013*

**Probability**

There is a woman that has a 40% chance of being in Casper recently, a 30% chance of being in Denver and a 27% chance that she has been to both. Find the probablility that she has been to Casper if she has been to Denver.
*July 29, 2013*

**math**

the square root of 0.0256/25
*June 24, 2013*

**algebra**

Write an equation in the form y = mx + b for the line that has a slope of 1/2 and contains the point (12, 3).
*June 18, 2013*

**algebra**

Alejandro is the manager of a catering business for private parties. The business charges a set-up fee of $40.00 per event and $8.00 per plate served at the party. Let c represent the total charges for the catering services and p represent the number of plates served at the ...
*June 16, 2013*

**algebra**

Simone rented a truck to move to a new apartment last month. The rental company charges a rental fee of $25.00 plus $0.50 per mile. Which of the following best represents the y-intercept in this situation? numbers of days of rentals numbers of gallon of gas used 0.50 fee per ...
*June 16, 2013*

**algebra**

Last spring Steve joined a health club. The club charges a one-time enrollment fee of $150.00 plus a $25.00 monthly fee. Which of these best represents the independent variable in this situation?
*June 16, 2013*

**BUSINESS**

The sales department tells management that they can increase revenue by 20 percent by increasing sales 20 percent, but the production department says that to achieve that number of units, they will have to buy a new piece of equipment that will add $200,000 to the appropriate ...
*June 5, 2013*

**chemistry **

a sample of 15.00 g of an unkown metal chloride, MCl2 is dissolved in 75.0 mL water. the boiling point of the resulting solution is measured at 102.37 degrees C. what is the identity of the metal M.
*May 13, 2013*

**chemistry**

m= 75 mL of water 0.001kg water= o.o75 of warer. 2.37 c = 3*0.512 c/m*m m=1.54297 to get moles 1.59297*0.075/1=0.119473 mol molar mass 15/ 0.119473= 125.551 125.551g -2* 35.45= 54.6514 making it manganese chloride would that be correct ?
*May 13, 2013*

**chemistry**

A compound was found to be composed of the following amounts of elements: 20.00% wt% C, 26.64wt% O, 46.65 wt%N, and 6.71wt%H. A 6.125 grams sample of this compound dissolved in 46.205 grams of water as a solution was found to have a freezing point of -3.260C. The density of ...
*April 25, 2013*

**Physics**

Same thing here :(
*April 11, 2013*

**Math ( Number Theory )**

How many numbers from 1 to 1000 inclusive can be expressed as the sum of k >= 2 consecutive positive integers for some value of k ? Sorry to post question from Brilliant, I got 997 integers, but it's wrong. If you think you can answer ...
*April 9, 2013*

**math**

Find all roots of the equation ln(4-x^2)=x correct to 8 decimal places. List all successive approximations.
*April 3, 2013*

**math**

5/24 feet long because if you divide 5/8 by 3 you simply multiply 5/8 times 1/3 and that is how you get the answer
*April 3, 2013*

**math**

It is noon. A secret agent is driving a jeep through the desert in the tiny principality of Alta Loma. He is 32km from the nearest point on a straight, paved road. Down the road 16km is a power plant in which a band of international terrorists has placed a time bomb set to ...
*April 3, 2013*

**math**

When at rest, two trains have sirens that emit a frequency of 300 Hz. The trains travel toward one another and toward an observer stationed between them. One of the trains moves at 30.0 m/s, and the observer hears a beat frequency of 3.6 beats per second. What is the speed of ...
*April 2, 2013*

**Chemistry **

the number of moles that contains 5.13x1022 atoms of manganese
*March 31, 2013*

**soanish**

he following question about Gabriel García Márquez. ¿Qué suceso importante aconteció para Márquez en 1982? a. publicó la novela “Cien años de solerdad” c. escribió sus obras mas importantes b. se le otorg...
*March 29, 2013*

**spanish**

¿Cuál de los siguientes NO ES uno de los autores latinoamericanos que ganó el Premio Nobel? a. Miguel Angel Asturias c. Jorge Luis Borges b. Gabriela Mistral d. Pablo Neruda
*March 29, 2013*

**govenment**

When crafting the new Constitution, the Framers drew from their experiences with which of the following? a. the governments of ancient Greece and Rome b. the writings of Rousseau and Locke c. their own State governments d. all of the above
*March 28, 2013*

**govenment**

The government set up by the Articles of Confederation had a. no legislative or judicial branch. b. only a legislative and an executive branch. c. only a legislative branch, consisting of a unicameral Congress. d. only a legislative branch, consisting of a bicameral Congress.
*March 28, 2013*

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