Monday

February 8, 2016
Total # Posts: 2,352

**chem**

Benzaldehyde, C6H5CHO}, has a normal boiling point of 179.0 C and a critical point at 422 C and 45.9 atm. Using a phase diagram, estimate its vapor pressure at 125 Degrees I'm directing it up again to Dr. Bob. (or anyone else who can help) **** If the boiling point (179) ...
*February 12, 2010*

**chemistry**

that was me who posted the comment above. my friend had the same question.
*February 12, 2010*

**chemistry**

1.) How much ethanol, C2H5OH, in liters (d=0.789g/ml) must be dissolved in water to produce 190.5 of 1.65 M C2H5OH? (Molarity problem.) 2.) How much concentrated hydrochloric acid solution (36.0% HCl by mass, d = 1.18g/mL}), in milliliters, is required to produce 11.0 L of 0....
*February 12, 2010*

**english**

I'm black,approx. 6" square,I have a hole in the middle ,and my sides go round and round
*February 11, 2010*

**History-PLEASE HELP**

Thank you soooo much!!
*February 11, 2010*

**History-PLEASE HELP**

I am stuck on a homework assignment and am having a hard time finding information on this topic. Can someone please please help!! Why is Kenneth Clark’s interpretation of the African mask ethnocentric?
*February 11, 2010*

**math**

ok, I realize that I should cut each remaining square into 9 quadrants leaving the middle open of each of them. Now, I just dont know how to get the percent of the original square that remains in stage 3.
*February 10, 2010*

**math**

Hello, Here is a question with something i've never heard of. These are the first two stages of a fractal known as the Sierpinski carpet. The carpet begins with a square (stage 1). The square is cut into 9 congruent squares and the middle square is removed (stage 2). Draw ...
*February 10, 2010*

**MATH**

On the xy-coordinate plane, point O is the origin. Suppose vector OE=(3,8) and vector OF=(-2,-4). What ordered pair represents vector EF? I tried graphing them but they don't even end up in the same quadrant. Not sure what to do..
*February 10, 2010*

**MATH**

Oh, so you had to find a pattern... Thanks
*February 10, 2010*

**MATH**

Hello, This figure shows the number of segments used to form longer and longer rows of squares. It shows that 1 square has 4 segments 2 squars has 7 segments and 3 squares has 10 segments. The question is how many segments will be in a row with 100 squares? Thought maybe a ...
*February 10, 2010*

**Math**

Oh thanks!
*February 10, 2010*

**Math**

For 5 consecutive days, the price of a lamp in jill's store is reduced by 10% from the previous day's price. At the end of the fifth day, by what percetage will the price of the lamp have been reduced from its initial price? I'm not sure where to begin since I don...
*February 10, 2010*

**MATH**

Hello I have to draw a pentagon with 30 square units on graph paper. My question is how can I get 30 square units if the slanted sides are not full squares?
*February 7, 2010*

**math repost Please Help!**

Hello, In a class of 24 students, every student flips fairly two coins 40 times each and records the results. Assume that the class obtained the expected results when they conducted the experiment. a. Make a bar graph illustrating the combined class results b. explain why an ...
*February 7, 2010*

**Math**

Patricia's teacher asked her to find the perimeter of the school's rectangular parking lot. After school, patricia walks along the short side of the lot and finds it is 50 yards long. She then walks diagonally from one corner of the rectangle to the other and throught ...
*February 7, 2010*

**math**

Ok you have to write a system of equations. x+y=40 2x+4y=100 y=40-x 2x+4(40-x)=100 solve: X=30 Y=10 then 30+y = 40 y=10
*February 7, 2010*

**MATH**

Hello, In a class of 24 students, every student flips fairly two coins 40 times each and records the results. Assume that the class obtained the expected results when they conducted the experiment. a. Make a bar graph illustrating the combined class results b. explain why an ...
*February 7, 2010*

**algebra**

Jennifer is twice as old as Ramon. The sum of their ages 7 years ago was 13. How old are they now?
*February 6, 2010*

**math**

Hello, A ship's movements are being tracked on a radar screen. The ship is first seen on point a with coordinates (-5,8) 1. It moves along vector AB represented by the ordered pair (-6,-1) 2. Then it travels along vector BC represented by the ordered pair (4,-3) 3. Finally...
*February 6, 2010*

**Math**

Ok, thanks. But how did you get 12 and 5?
*February 6, 2010*

**Math**

Hello, I'm not sure how to go about this question. To get to work on the first day, Jose has the following directions. Travel 15 miles due East. Turn right and travel 12 miles due south. Turn right again and travel 10 miles due West. If Jose could travel in a straight line...
*February 6, 2010*

**Math**

ahh, so simple in hind sight
*February 6, 2010*

**Math**

Hello, I can't find a pattern to answer this question, can you help? The beginning of the fibonacci number sequence is listed below: 1,1,2,3,5,8,13,...... What is the smallest term in the sequence which has a value greater than 100?
*February 6, 2010*

**physics**

PE=(13/3)k(Q^2)/a
*February 3, 2010*

**Math**

Solve by the elimination method. 2r-5s = -11 5r + 2s = 16
*January 31, 2010*

**Math**

Find the indicated outputs for f(x)= 5x^2-5x. F(0) = 0 f(-1)= 1 f(2)= 45 is this right?
*January 31, 2010*

**Elimination Method...**

Solve by eliminatin method. 2r-5s= -11 5r+2s= 16
*January 31, 2010*

**equal group riddles**

i am a number between 20 and 30.when you put me into 6 equal groups;there is an even number in each group and 1 is left over.what number am i
*January 30, 2010*

**Finance**

2142
*January 27, 2010*

**Calculus**

eeee
*January 27, 2010*

**math**

In how many ways can 7 basketball players of different heights line up in a single row so that no player is standing between 2 people taller than she is?
*January 27, 2010*

**chemistry**

22%
*January 24, 2010*

**Math-Fractions**

How would I solve these two problems. (We have to simplify our answer) 5/7 divided by 8/21 12/7 divided by 9/21
*January 19, 2010*

**Elementary Math**

On a number where would 4/3 go? Would it go one third the way between 3 and 4? Where would 5/3 go?
*January 17, 2010*

**Molarity**

Determine the molarity and normality of a solution prepared by dissolving 55 mg of sodium bicarbonate (NaHCO3) in 750 mL of water.
*January 14, 2010*

**Precal**

use graphic techiques in radians I found that it is roughly equal to -.5 sin [ 20.42036^-1(x + 40.84071)pi ] + 1
*January 14, 2010*

**Precal**

I do not understand how to do this problem ((sin^3 A + cos^3 A)/(sin A + cos A) ) = 1 - sin A cos A note that all the trig terms are closed right after there A's example sin A cos A = sin (A) cos (A) I wrote it out like this 0 = - sin^6 A - cos^6 A + 2sin^3 A cos^3 A - ...
*January 14, 2010*

**Physics**

I'm having some trouble with this question A 4200-kg rocket is traveling in outer space with a velocity of 120m/s toward the Sun. It needs to alter its course by 23 degrees, which can be done by shooting is rockets briefly in a direction perpendicular to it’s original...
*January 13, 2010*

**Physics**

A 16.0 - kg descends a slide 2.50 m high and reaches teh bottom with a speed of 2.25 m/s. How much thermal energy due to firciton was generated in the process? for this I keep on getting 432.5 J but the back of the book tells me that the answer is 352 J and I do not see how to...
*January 12, 2010*

**physics**

A charge of 2.4 nC and a charge of 5.0 nC are separated by 33.30 cm. Find the equilibrium position for a -4.1 nC charge.
*January 11, 2010*

**physics**

Calculate the net charge on a substance consisting of a combination of 6.8 multiplied by 1013 protons and 4.6 multiplied by 1013 electrons.
*January 11, 2010*

**precal**

given cscx= -3 and tanx>0 find cosx
*January 10, 2010*

**precal**

from {0,2pie} what are the solutions of tan x/4= square root of 3/3
*January 10, 2010*

**precal**

from {o, 2pie} what are the solutions of cos(squared)x- cos2x=0
*January 10, 2010*

**urgent precal**

What is cosx/ (secx-1) not in fractional form?
*January 10, 2010*

**precal**

yes i meant to have it with parantheses
*January 10, 2010*

**precal**

rewrite cosx/secx-1 not in fractional form
*January 10, 2010*

**chemistry**

In any chemical reaction, the quantities that are preserved are what? A. the number of moles and the volumes B. the number of molecules and the volumes C. mass and number of atoms D. mass and moles
*January 8, 2010*

**AP World History**

How can I show Change and Continuity in the American Environment between 600 AD - 1750 AD?
*January 6, 2010*

**Biology**

the first one is b. there is no general relationship.
*January 6, 2010*

**Math**

A group of nine students has a mean of 3.5 people in their households. Make a line plot showing an example of this data set
*January 5, 2010*

**science**

When is the Earth farthest from the sun?
*January 5, 2010*

**Physics**

The Olympic diver completes 3.5 somersaults in 1.7 seconds. What is the average angular speed (in rad/s) of the diver?
*December 21, 2009*

**chemistry**

The addition of a dilute hydrobromic acid would clearly distinguish solutions of a. barium nitrate and sodium sulfate b. lead nitrate and silver nitrate c. mercury(I) nitrate and silver nitrate d. silver nitrate and calcium sulfate e. calcium nitrate and barium nitrate
*December 18, 2009*

**AP Physics B (Heat Engines)**

I know that efficiency is e = |W|/|QH| were the H is the subscript I know that 900 MW is a value of power which is not work I know that |QH| is 2.8 E8 J/kg but I do not like the units for this, J/kg, as I thought Q was measured in joules only... How do I find the work done?
*December 16, 2009*

**AP Physics B (Heat Engines)**

18. (II) At a steam power plant, steam engines work in pairs, the heat output of the first one being the approximate ehat input of the second. Th eoperating temeprautres of the first are 680 degrees C and 430 degrees C, and of the second 415 degrees C and 280 degrees C. If the...
*December 16, 2009*

**pre al**

how do you find surface area
*December 15, 2009*

**SCIENCE**

What is the movement of a water particle in a wave called?
*December 14, 2009*

**science**

The movement of a water particle in a wave is called what?
*December 14, 2009*

**physics**

An aluminum cylinder weighs 1.03 N. When this same cylinder is completely submerged in alcohol, the volume of the displaced alcohol is 3.90 x 10-5 m3. If the cylinder is suspended from a scale while submerged in the alcohol, the scale reading is 0.730 N. What is the specific ...
*December 13, 2009*

**History**

Why do we need taxes? Could someone tell me in two paragraphs besides that we need it for roads and schools
*December 12, 2009*

**college**

what strategies can be incorporate into effective visual element into business presentations
*December 11, 2009*

**algebra 1**

Use the point-slope form to write an equation of the line with the given slope and point. m = 4, passes through (4, 6)
*December 10, 2009*

**PreCalc**

please h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 6 0 4 8 7 4 9 0
*December 10, 2009*

**Pre Calc**

I do not see why I got two different equations for my answer A weight attached to the end of along spring is bounicng up and down. As it bounces, its distance from the floor varies sinusoidally with time. You start a stopwatch. When the stopwatch reads 0.3 s, the weight first ...
*December 10, 2009*

**biology**

what functional groups appear in CH3CH2CH2Br
*December 10, 2009*

**algebra**

3[5-(2x+1(2))]= 3[5-(2x+2)] 3[5-2x-2]= 3[3-2x]= 9-6x
*December 10, 2009*

**spanish**

what is the correct possessive adjective for ¿Es mi clase de español?
*December 9, 2009*

**english**

Did you like “Usher”? How successful was Poe’s use of Gothic devices in creating an atmosphere of dread?
*December 7, 2009*

**Calc 3**

The actual span of the base of the dome is 143 feet. 1) Use cylindrical coordinates to write the surface of the dome as a function of the distance from the center of the base; that is find z = f (r) . 2) Use your function to find the height of the dome; that is what is f (0...
*December 7, 2009*

**Pre Calc**

Naturalists findthat the populations of some kinds of predatory animals vary periodically. Assume that the population of foxes in a certain forext vareis sinusoidally iwth time. REcord started being kept when time t = 0 years. A minimum number, 200 foxes, occurred when t = 2.9...
*December 6, 2009*

**PreCalc**

never mind
*December 6, 2009*

**PreCalc**

so what is the equation of the line??? h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 6 0 1 4 7 1 4 4 I understood this y = 120 + 8sin((pi)/35 - (5pi)/4)=120 were do i go from here THANKS!!!
*December 6, 2009*

**Math**

What does this notation mean =^-1 equal sign raised to negative one power
*December 6, 2009*

**TOBOBPURSLEY**

I thought phase shift was theta over omega correct??? and the period equals two pi over omega 40 min = (2pi)/omega omgea = pi/20 min phase shift = theta over omega phase sift = (20?)/pi min now you said phase shift was (35 pi)/40 I do not see why I appologize i made a spelling...
*December 6, 2009*

**TOBOBPURSLEY**

how do we now that the phase shift is (35pi)/40 please explain THANKS
*December 6, 2009*

**PreCalculus**

I have a question I do not think anybody answered it Researches find a creature form an alienplanet. Its body temperature is varying sinusoidally with time. 35 min after they start timing, it reaches a high of 120 F. 20 min after that it reaches its next low, 104 F. How do I ...
*December 6, 2009*

**PreCalculus**

How do i find teh phase shift in this problem Naturalists find that the populations fo some kinds of predatory animals vary periodically. Assume that the population of foxes in a certain forest varies sinusoidally with time. Records started being kept when time t = 0 years. A ...
*December 3, 2009*

**8th grade**

how did the survivours of Krakatoa recieve help
*December 3, 2009*

**FINANCE**

go on th eenternet
*December 3, 2009*

**Precalculus**

tangent theta is equal to the derivative of sine theta over the derivative of cosine theta?
*December 2, 2009*

**Precalculus**

Sorry ok I was talking about on the unit circle how come the slope of the reference line (say if you were to angle pi/2, the reference line would be the positive y axis from y equals zero to y equals one, I think this line is called this, like if you were to draw pi/4 on the ...
*December 2, 2009*

**PreCalculus**

h t t p : / / w w w . j i s k h a . c o m / d i s p l a y . c g i ? i d = 1 2 5 9 7 1 4 6 2 0
*December 1, 2009*

**PreCalculus**

Ok I know that the slope of a straight line is the same thing as x with a dot aboce it or simply the first derivative of x on the unit circle tangent gives you the slope of the reference line right? This can be expressed using the notation expressed above but how? Thanks!
*December 1, 2009*

**physics**

On a cold winter day when the temperature is -20 degrees celsius, what is the amount of heat needed to warm internal body temp(37) the .5 L of air exchanged with each breath? Specific heat of air is 1020 J/(kg K) and that 1.0L air has a mass of 1.3g. Please help!! I dont know ...
*November 30, 2009*

**Statistics (Probability)**

I have a q
*November 30, 2009*

**Psychology**

its my friend, we both have the same problems and try to see if we can get helped
*November 28, 2009*

**Psychology**

Could someone see if I got any of the questions wrong. I feel that some questions have multiple answers but there is only one that is correct. Please help. thanks a lot State whether each scenario is an example of assimilation or accommodation. 1. A child has always used a ...
*November 28, 2009*

**4th grade**

4th grader asks how to solve 8100/?=90
*November 19, 2009*

**chemistry**

a resting person requires 14.5 L of O2 per hour to maintain metabolic activities. Such a person breathes in 0.50 L of air at approximately 20 degrees C with each breath. The inhaled air is 20.9%O2 while the exhaled air is 16.3% O2. (a) how many breaths per minute does a ...
*November 19, 2009*

**math**

1/n^2=0.0278
*November 16, 2009*

**Networking**

Jack is setting up a new FTP server that is running the Windows XP operating system. This FTP server will be shared by seven different corporate departments, each identified by a user group, but access is to be restricted by department. The Domain Administrators, Departmental ...
*November 15, 2009*

**Math**

some of the worst math I've ever seen
*November 15, 2009*

**Calc**

A common inhabitant of human intestines is the bacterium Escherichia coli. A cell of this bacterium in a nutrient-broth medium divides into two cells every 20 minutes. The initial population of a culture is 59 cells. (The tolerance is 1% unless your instructor states otherwise...
*November 8, 2009*

**algebra**

A wholesaler mixed coffee beans worth $6/kg with another kind worth $8.80/kg. The 16kg mixture was worth $6.70/kg. How many kilograms of each type was used?
*November 7, 2009*

**5th grade Language**

1.i and 5 2.named and blaze 3.was and once 4.wouldn't and out 5.first and filly 6.hoarse and croaked
*November 5, 2009*

**Physics**

Projectile motion equation: y=xtan(è)-(gx^2)/[2(ucos(è))^2] where è=39.5 deg., u -34.9 met/sec & g=9.8 met/sec^2. On substitution and solving for y=0, you can get the horizontal range as 122.003 met. and thus the time required would be = 122.003/(ucos(&...
*November 5, 2009*