Friday

November 27, 2015
Total # Posts: 1,398

**physics**

a laser beam with wavelength 632.8nm is incident normal to the plane of a diffraction grating with a slit separation d=2000nm. if the diffraction pattern is viewed on a screen 1m from the grating, find the distance separating the first, second, adn third maxima in the pattern.
*October 30, 2011*

**speech**

I am doing a speech on how to decorate a cupcake. But.. i do not know how to start it. I need an attention grabber any ideas?
*October 29, 2011*

**physics**

When the Sun is directly overhead, a hawk dives toward the ground at a speed of 3.07 m/s. If the direction of his motion is at an angle of 57.2 ◦ below the horizontal, calculate the speed of his shadow along the ground. Answer in units of m/s
*October 27, 2011*

**calculus**

im having so much trouble figuring out how to get these answers. i already know the answers i just need to figure out how to get them... directions: find the points of inflection and discuss the concavity of the graph of the function... 1. f(x)=(1/2)x^4+2x^3 2. f(x)=x^3-6x^2+...
*October 23, 2011*

**Chemistry**

Sorry, I need to clarify. My question is why does a precipitate begin to form even though the solution is still basic (before enough HCl is added to make it acidic). Enough HCl is added to make the solution acidic, then it is submerged in an ice bath where the precipitate ...
*October 23, 2011*

**Chemistry**

You isolate an acidic compound in an experiment by first separating it from the organic layer. Then you have a solution containing a salt of an acid. You acidify it using concentrated HCl. A precipitation begins to form while the solution is still basic.. why? You continue the...
*October 23, 2011*

**Biology**

35.49
*October 20, 2011*

**Chemistry**

Would this be the quickest/most efficient method: Take a small test tube, add roughly 1mL of water. Add a single drop of one of the unknown solutions. If the drop is miscible with water then it is from the aqueous phase; if it sinks to the bottom (or floats) it is the organic ...
*October 19, 2011*

**Chemistry**

During an experiment involving separation, you forget to label your beakers and you are unsure of which beaker contains the aqueous layer and which contains the organic layer. How could you quickly and efficiently determine which one is the aqueous layer?
*October 19, 2011*

**Korean**

I am Korean and your translation is right. However, your grammar should be changed into He is always unlucky in love :)
*October 19, 2011*

**Algebra 1**

oh wait never mind. I see my mistake now. Thanks for the help.
*October 18, 2011*

**Algebra 1**

5. And wouldn't it be -12n?
*October 18, 2011*

**Algebra 1**

3n+40=-6(-2n+1)+1
*October 18, 2011*

**Algebra 1**

Thank you so much.
*October 18, 2011*

**Fibonacci Numbers**

I need to find f24. I know F23=28657 and f25=75025. I have figured out that F24 is 46368 using F(n)=F(n-1)+F(n-2). My problme is asking me for two values of n for which Fn=n. I do not understand what it is asking.
*October 17, 2011*

**calculus**

water is poured into a conical paper cup so that the height increases at the constant rate of 1 inch per second. if the cup is 6 inches tall and its top has a radius of 2 inches, how fast is the volume of water in the cup increasing when the height is 3 inches?
*October 16, 2011*

**calculus**

the cross section of a 5-ft long trough is an isosceles trapezoid with a 2 foot lower base, a 3-foot upper base, and an altitude of 2 feet. water is running into the trough at a rate of 1 cubic foot per minute. how fast is the water level rising when the water is 1 foot deep?
*October 16, 2011*

**math**

A ladder is resting against a wall. the foot of the ladder is 8 feet from the wall, and the top of the ladder is 19 feet from the ground. FIND THE slope of the ladder
*October 16, 2011*

**Fibonacci Numbers**

I posted the question several days ago and Mathmate helped to guide me along. I am just unsure if I do not understand what he is saying or if I did complete the problem right. I would appreciate any input. 1.618034 - -.618034 = 2.236068/sqrt 5 = 1.00000 I understand how to use...
*October 15, 2011*

**calculus**

a large ferris wheel is 100 feet in diameter and rises 10 feet off the ground. each revolution of the wheel takes 30 seconds. A) express the vertical distance "H" of the seat off the ground as a function of time "t" if t=0 corresponds to a time when the ...
*October 13, 2011*

**Biology**

What is the first step in replication?
*October 12, 2011*

**Fibonacci Numbers: Understand one part not another**

I understand how to use a calculator to write the decimal point using the golden ratio which is 1.618034 and the conjugate is -.618034. I also know that the relationship between the decimal expansions is that everything to the right of the decimal is the same except one is neg...
*October 12, 2011*

**Check Fib. Number problem please**

For any prime number p except 2 and 5, either Fp-1 or fp+1 is divisible by p. If I showed that this is true for p=7, the answer should be F8---is this correct because f8 is 21. P=11 would be divisible by 55 which is F10.
*October 10, 2011*

**physics**

is the speed of the cannon ball relative to the car or the ground??
*October 10, 2011*

**Chemistry**

A .1360 g sample of a mixture of magnesium and calcium carbonates when treated with HCL evolves 32.25 cm cubed of carbon dioxed measured dry at STP. Calculate the percent of magnesium carbonate in the mixutre.
*October 4, 2011*

**chemistry**

What is the pH of a solution prpared by mixing 50.0 ml of .200 M HCLO4 with 10.0 ml of .100 M KOH
*October 4, 2011*

**Physics**

A rope attached to an engine pulls a 240 Newton crate up an 14.7 degree ramp at a constant speed. The coefficient of kinetic friction for the surfaces of the crate and ramp is .32. What is the magnitude of the force that the rope exerts on the crate parallel to the ramp? (...
*October 4, 2011*

**math**

problem> mystery numbers: Bob is thinking of 2 numbers their sum is 26. their product is 165. what numbers is bob thinking about?
*October 3, 2011*

**Geology**

What is the defining characteristic of the troposphere? (Straight forward answers please & thank you)
*October 2, 2011*

**Geology**

A thunderstorm tends to be more severe and have a longer duration if the axis of the storm is: tilted, perpendicular to the ground, or it makes no difference. (Straight forward answers, if possible use the answer choices provided please & thank you)
*October 2, 2011*

**Geology**

How is a mid-latitude cyclone formed: thunderstorms on the west side of an occluded front, frontal systems in association with the Jet Stream, a lot of hot air, or cyclonic circulation around a sub-tropical high? (Straight forward answers, if possible use the answer choices ...
*October 2, 2011*

**Geology**

which 2 would create a low pressure at the surface? warm temp., cold temp., air moving through a terrain constriction, or air moving out of a terrain constriction. What is the main reason hail is not associated with tropical thunderstorms: lack of sufficient moisture in the ...
*October 2, 2011*

**Geology**

How is a mid-latitude cyclone formed
*October 2, 2011*

**Geology**

When will a thunderstorm tend to be more severe and have a longer duration in reference to the axis of a storm.
*October 2, 2011*

**Geology**

Winds blow whenever there are: cold temperatures, pressure inequalities in the atmosphere, or the earth rotates on its axis
*October 2, 2011*

**Geology**

When a hurricane approches a costal area the damage from the storm surge is greater if it occurs: low tide, high tide, tide makes no difference? The dew point of a prcel of air refers to: its elevation above the surface, the temp. at which condesation will occur, the pressure ...
*October 2, 2011*

**Geology**

why do fall winds always warm as they descend the lee side of a mountain
*October 2, 2011*

**redwine**

what measures does patrick henry say the colonists have already tried in their dealings with england?
*September 29, 2011*

**Science **

I have 2 questions. 1.) Is there a powder that just contains insoluble fiber. I know that Benifiber and many other products contain soluble fiber or both soluble and insoluble fiber. But for the experament I have put together i need an insoluble fiber powder ONLY! I have not ...
*September 28, 2011*

**Math**

Find dy/dx by implicit differentiation. cot(y) = 4x − 6y
*September 28, 2011*

**calculus**

Let P= (V^2)R / (R+r)^2 Calculate dP/dr, assuming that r is variable and R is constant.
*September 26, 2011*

**Chemistry**

Which of the following statements are false regarding using a solid drying agent? (select all that apply) a) Water can be present due to isolation and/or purification conditions b) A good drying agent must be soluble in organic solvent c) One type of drying agent is sodium ...
*September 26, 2011*

**Chemistry**

Which of the following statements are true regarding suction filtration? (select all that apply) a) Product should always be rinsed with cold water b) The filter flask can be held in place with your hand c) When filtering is complete you should remove the suction hose and then...
*September 26, 2011*

**physics**

A certain car is capable of accelerating at a uniform rate of .94m/s^2. What is the magnitude of the car's displacement as it accelerates uniformly from a speed of 87km/h to one of 97km/h? Answer in units of m.
*September 24, 2011*

**physics**

need help with the following question. if earth has a mass of 6.0*10^24 kg and a radius 6.4*10^6 m: a) find the change in gravitational potential energy of a meteorite of mass 150 kg as it moves from an infinite distance to the earth's surface. b) with what speed does the ...
*September 24, 2011*

**math**

so what is the opposite of a professional eater
*September 22, 2011*

**chemistryyy**

Answer the following two questions about the equivalence point for the titration of 27.8 mL of 0.235 M hypobromous acid (pKa = 8.64) with 0.214 M KOH. 1)Predict if the solution will be acidic, basic or neutral at the equivalence point. 2)Calculate the pH of the solution at the...
*September 21, 2011*

**chemistryyy**

Answer the following two questions about the equivalence point for the titration of 27.8 mL of 0.235 M hypobromous acid (pKa = 8.64) with 0.214 M KOH. 1)Predict if the solution will be acidic, basic or neutral at the equivalence point. 2)Calculate the pH of the solution at the...
*September 21, 2011*

**CHEMISTRY**

A buffer that is 0.271 M in acid, HA, and 0.150 M in the potassium salt of its conjugate base, KA, has a pH of 2.85. What is the pH of the buffer after 130. mL of 0.155 M LiOH is added to 0.650 L of this buffer? Assume that the volumes are additive.
*September 21, 2011*

**CHEMISTRY**

A buffer that is 0.271 M in acid, HA, and 0.150 M in the potassium salt of its conjugate base, KA, has a pH of 2.85. What is the pH of the buffer after 130. mL of 0.155 M LiOH is added to 0.650 L of this buffer? Assume that the volumes are additive.
*September 21, 2011*

**Math: Different Forms of Linear Functions**

y< x/2 -6 How do I make this into a table and then into ordered pairs?
*September 15, 2011*

**Math: Different Forms of Linear Functions**

The output is 6 less than one-half of the input
*September 15, 2011*

**chemistry**

What is Delta H rxn for the following chemical reaction? H2O(l) + CCl4(l)-> COCl2(g) + 2HCl(g)
*September 4, 2011*

**math**

cos(2x)
*September 1, 2011*

**math**

solve for sinx=cos2x (between 0 and 2pi)
*September 1, 2011*

**calculus**

find cosx and sinx if tanx = 4
*September 1, 2011*

**Math**

You'ree Welcomee 2nd Graderss![:
*September 1, 2011*

**Math**

7th* Hahaha The answer is onee![:
*September 1, 2011*

**Math**

Highest number minus the lowest. Which would be 5-4 You're Welcome!(; Btw I'm like a 7h graderr.:P
*September 1, 2011*

**calculus**

The side of a square is measured to be 12 inches with a possible error of ±0.02 inch in that measurement. If x is the exact length of the side of the square, express this difference as an absolute value inequality and solve. Then find the interval expressing the range ...
*August 29, 2011*

**Bio**

What is it called when b=d and r=0? A. iteroarity B. semelparity C. zero population growth D. cohort E. a survivorship curve I think it is E but I would greatly appreciate a teacher's input!
*August 27, 2011*

**Chemistry**

an atom is to an element as a compound is to a?
*August 26, 2011*

**physical science**

305
*August 19, 2011*

**English**

Thank you! It's really nice that you do this whole homework help for free. A lot of websites charge for stuff like that! I appreciate it immensely:) I'll be keeping this website in mind when I have Algebra 3-4 to keep up with:P
*August 2, 2011*

**English**

What tools are in a "writing toolbox"?
*August 2, 2011*

**Medical Terminology**

Need help identifying 15 medical terms that would be unfamiliar to non-medical persons. Also providing singular and plural forms of selected medical terms. This is a 47-year-old male who was in his usual state of health until early this evening when he developed an acute ...
*August 2, 2011*

**Trigenometry**

VERY URGENT! PLEASE HELP SOLVE! tan(x)+1=sqrt(3)+sqrt(3)cot(x)as well as sin(2x)= 2 cos^(x) 4cos2(x) = 8sin(x)cos(X)
*August 1, 2011*

**algebra**

4000
*July 27, 2011*

**intermediate icd 9 cm coding**

What are the codes for Intrauterine pregnancy, spontaneous delivery, single live born?
*July 25, 2011*

**Med terms**

dysphnea=dyspnea.....oops
*July 12, 2011*

**Med terms**

afonia=pneumonia eupnia=apnea dysphnea=dyspnes DOT=DOB ventolator=ventilator
*July 12, 2011*

**Med terms**

I am having troubles finding all 10 mistakes and need some help. Inpatient Progress Report Attending Physician: Moreover, Cindy Patient: Stephen R. Peters DOT: 03/01/19XX CHIEF COMPLAINT: This 53-year-old man visited the outpatient clinic for dyspnea and recurrent coughing. ...
*July 12, 2011*

**physics**

Physics: maximum force that can be applied to move an object? What is the maximum force F which can be exerted? Given: The friction between the block with mass 14 kg and the wedge with mass 16 kg is 0.19 . The surface between the wedge with mass 16 kg and the horizontal plane ...
*June 16, 2011*

**Life science**

True or false, the healthiest position to sleep on for the baby while you're pregnant is on your back
*June 5, 2011*

**Life science**

How many teeth does a child have and how many teeth do adults have?
*June 5, 2011*

**Math puzzle**

2•2=4, 7•3=21, 4•3=12, 3•2=6 ... 4+21=25, 25+12= 37, 37+3= 40, 40+4=44, 44+6= 50... I'm no math genius but I hope that I helped, the answer is 50.
*June 5, 2011*

**propability**

there are 40 tags numbered 1 through 40 in a bag. what is the probability that Glenn will randomly pick a multiple of 5 and than a multiple of 9 without replacing the first one?
*June 1, 2011*

**Physics (Fill in the Blanks)**

1. The last stage of a giant star is ____ 2. The path of a satellite is called ____ 3. The size of the Sun is the result of the "tug of war" between two opposing processes, nuclear fusion and ____ contraction Thanks :)
*May 13, 2011*

**Physics**

Two students are on a balcony 20.5 m above the street. One student throws a ball (ball 1) vertically downward at 11.1 m/s; at the same instant, the other student throws a ball (ball 2) vertically upward at the same speed. The second ball just misses the balcony on the way down...
*May 12, 2011*

**Chem**

Calculate the standard cell voltage, Eo, for the following reactions. Include the sign of the voltage in your answers. (a) Fe2+(aq) + Pb(s) --> Pb2+(aq) + Fe(s)
*May 10, 2011*

**Chemistry**

2 Ag+(aq) + Fe(s) --> 2 Ag(s) + Fe2+(aq) Which electrode is the anode, and which is the cathode. and In which directions do the cations and anions migrate through the solution? cations thanks
*May 10, 2011*

**business law**

Mary and Celia open a boutique, they hire independent contractors. When they are not selling Mary and Celia want the I.C's to do inventory and clean up the boutique. Mary and Celia also set the working hourse.. does these factors affect theri status as independent ...
*May 9, 2011*

**chemistry**

In the reaction 2SO2 (g) + O2 (g) 2SO3 (g), which change would cause the greatest increase in the concentration of SO3?
*May 3, 2011*

**Brief Calculus**

its supposed to be 1/v^7
*May 3, 2011*

**Brief Calculus**

Evaluate the integral. HINT [See Example 2 and 4.] (Remember to use ln |u| where appropriate.) (1/v7 + 5/v) dv
*May 3, 2011*

**Calc**

Find f(x) if f(1) = −1 and the tangent line at (x, f(x)) has slope7ex + 6. F(x)=
*May 3, 2011*

**Calculus**

no it is just as the denominator is one with the variable 4x^5 and 2x^7 not 1/25 raised to the 6th or 1/2 raised to the 7th
*May 3, 2011*

**Calculus**

Use fundamental theorem of calculus: Int(pi/2_pi) of e^(sin(q))*cos(q)dq
*April 28, 2011*

**Chemistry**

In the following reaction, how many grams of ammonia (NH3) will produce 300 grams of N2? 4NH3 + 6NO d 5N2 + 6H2O
*April 27, 2011*

**Algebra**

Explain the difference in answers between the following exponential expressions. Include the solutions? 7^2, -7^2,(-7)^2, and 7^-2
*April 27, 2011*

**English (Grade 5)**

Well I've got 8,2,9,3,1,6,10,4,7,5. Do you think this is correct?
*April 24, 2011*

**English (Grade 5)**

This is not in order. Please put the story about "The wishing well in order" 1. Today is a particularly busy day at the well. 2. This wishing well is very popular 3.It is New Years Day 4.Other People make wishes about their families. 5. For this reason the park will ...
*April 24, 2011*

**Religion and Spirituality**

What do you think is the moral of the story Tao of Forgiveness? Thank you :)
*April 24, 2011*

**Math**

determine one value of c that allows the trinomial cy^2 + 36y - 18 to be factored over the integers
*April 20, 2011*

**Math**

oh and the other rectangle is 1 by 5 ft
*April 20, 2011*

**Math**

1 by 8 is the dimensions I drew them both and divided the perimeters and then substitued starting from 1 and it worked the first time, but yeah the answer is 8
*April 20, 2011*

**Geometry**

how to you solve: the radius of circle Z is 13.5 units long. Find the length of each arc for the given angle measure. if the angle measure is 120 degrees?
*April 19, 2011*

**Calculus**

Hey, we covered limits at the beginning of the year, but I cannot remember how to do them at all. >>>what is the limit, as x approaches 2, of ((1/x )-(1/2))/(x-2)? Please go step by step!
*April 18, 2011*

**math**

a cross section of a hollow circular pipe shows that its inner diameter is 2 1/10inches and that the pipe is 3/5inch thick. what is the outside diameter
*April 18, 2011*

**economics**

Jerry will receive the following payments: 946 in year 3, 929 in year 5 and 958 in year 9. What is the purchasing power of the present value of these payments if the market interest rate is 17% per year and the inflation rate is 6% per year?
*April 17, 2011*