Saturday
February 13, 2016

# Posts by alex

Total # Posts: 3,266

physics
A point charge of 2.4 μC is located at the center of a spherical shell of radius 17 cm, which has a charge −2.4 μC uniformly distributed on its surface. Given: ke = 8.98755 × 109 Nm2/C2 . a)Find the electric field for all points outside the spherical ...
September 19, 2011

physics
Okay, when I took the quotient of the distance - r1 and r2-r1, I got 0.45 Then multiplied by Q gave me 3.6*10^-12 (I changed pC to C). Am I doing something wrong again? How did you come up with 0.3583?
September 18, 2011

physics
A charge of 8 pC is uniformly distributed throughout the volume between concentric spherical surfaces having radii of 1.7 cm and3.7 cm. What is the magnitude of the electric field 2.6 cm from the center of the surfaces? Let k_e=8.98755*10^9 N*m^2/C^2 I used the formula E=k_e(Q...
September 18, 2011

chemistry
A 150.0-mL sample of Solution A is diluted to a total volume of 423 mL to form Solution B. If the concentration of Solution A was originally 20.0 mg/L, what is the concentration (in mg/L) of Solution B?
September 18, 2011

chemistry
Calculate the concentration (in mg/L) of a solution formed by dissolving 5.000 g of solute in enough solvent to make 2.300 L of solution.
September 18, 2011

algebra 1
From a shipment of 350 light-bulbs, a sample of 70 was selected at random and tested. If 21 light-bulbs in the sample were found to be defective, how many defective light-bulbs would be expected in the entire shipment?
September 18, 2011

Physics
When the sun was directly overhead in Syene, why was it not directly overhead in Alexandria?
September 16, 2011

Chemistry
I am not sure if I have the right answer or not to the following question. One mole of NO2 would be produced from how many moles of molecular nitrogen> According the equation N2 + 202 > 2NO2. I was thinking maybe 2. Does anyone know if I am right or wrong. Thanks
September 15, 2011

How would you use a number line to round 148 to the nearest ten?
September 14, 2011

1. Which number does not round to 400? 347 369 413 448
September 14, 2011

8 remainder of 1
September 14, 2011

Tyrell says 753 rounds to 800. Sara says 753 rounds to 750. Who is correct? Explain.
September 14, 2011

math
Do 20+50 which is 70 then 5+9 which is 11 then add 70+11.
September 13, 2011

It's 40.
September 13, 2011

A Texas horned lizard laid 37 eggs in one place. To the nearest ten, about how many eggs did the lizard lay?
September 13, 2011

Does (4+5) + 2 = 9+2? Explain
September 12, 2011

College Physics
A)2 b)5.7 C)87.7 D) 76.4 E)4.5
September 12, 2011

MATH(order of operations help)
What is the only order of operations that does NOT proceed from the left to the right
September 9, 2011

Math
Find a formula and graph the function: A ferris wheel is 20 meters in diameter and boarded in the six oclock position from a platform that is 4 meters above the ground. The wheel completes one full revolution every 2 minutes. At t=0 you are in the twelve oclock position.
September 5, 2011

probability---normal distribution
population size=50 population mean= 80m standard deviation = 0.70m what proportion would have average meter of 89 or more? ---------------------------- now I know how to solve this problem if the question is worded "what proportion would have average meter Greater than 89...
September 4, 2011

trig
If sin T = 1/2, then the value of sinT ( sinT - cosecT ) is
September 3, 2011

chemistry
Magnesium metal reacts with HCl solution, liberating H2 gas and generating Mg2+ cations in solution. A 2.335-g sample of Mg metal is added to 50.0 mL of a 4.00 M HCl solution, and the reaction goes to completion. How many grams of H2 are formed?
September 1, 2011

language and barriers
It's not C.. I think in order to be a good ESL teacher you yourself have to set aside all the predjudice and what not that you yourself can think off...
August 31, 2011

Algebra
In a class of 110 students, 22 received the grade of A. what fraction of the students did not receive the grade A?
August 31, 2011

Child Care Managment
which of the following is is best suited to a formative assessment of progress? A, muscular strngth and endurance B body fat analysis C. Flexibility D awareness of selfand space. I think is A. But if Im wrong can somebody help me. thanks.
August 19, 2011

calculus
using tangent half substitution show that integral of sec(x)=ln(secx+tanx)
August 14, 2011

Math
x = 125
August 13, 2011

Math
There are 150 green marbles and 100 yellow marbles in a bag that contains 250 marbles. If only yellow marbles are added to the bag so that the probability of randomly drawing a yellow marble from the bag becomes 3/5, how many yellow marbles are in the bag?
August 13, 2011

Math
What are all values of x for which |2x-3| < 7 ?
August 13, 2011

Math
Sigourney Weaver's average rate going uphill was 80% of her average rate going downhill over the same route, and it took Sigourney Weaver 10 minutes longer to go up the hill than to go down the hill. What was the total number of minutes Sigourney Weaver spent going uphill ...
August 13, 2011

Physics
An artery branches into two smaller veins, identical arteries as shown in the diagram. The largest artery has a diameter of 10 mm. The two branches have the same diameter = 5 mm. The average speed of the blood in the main artery is given in the diagram. The blood has a density...
August 10, 2011

Physics
An artery branches into two smaller veins, identical arteries as shown in the diagram. The largest artery has a diameter of 10 mm. The two branches have the same diameter = 5 mm. The average speed of the blood in the main artery is given in the diagram. The blood has a density...
August 10, 2011

Math
What is the answer for this question: Divide 100 loaves of bread among five men so that the amounts are in aritmetic progression (increase by the same amount each time) and the sum of the 3 largest is 7 times the amount of the 2 smallest
August 4, 2011

Physics
Nevermind I was able to finally figure it out xP
August 2, 2011

Physics
You set out to design a car that uses the energy stored in a flywheel consisting of a uniform 103-kg cylinder of radius R that has a maximum angular speed of 450 rev/s. The flywheel must deliver an average of 1.70 MJ of energy for each kilometer of distance. Find the smallest ...
August 2, 2011

Calculus
Sales of Version 5.0 of a computer software package start out high and decrease exponentially. At time t, in years, the sales are s(t)=20e^-t thousands of dollars per year. After 2 years, Version 6.0 of the software is released and replaces Version 5.0. Assume that all income ...
July 28, 2011

Calculus
It is estimated that the demand for a manufacturer's product is increasing exponentially at an instantaneous rate of 5% per year. If the current demand is increasing by 4000 units per year and if the price remains fixed at \$850 per unit, how much revenue will the ...
July 24, 2011

Physics
Ah I see thank you, I had tried a different setup before which got me the wrong answer. But this helps a bunch thanks!
July 19, 2011

Physics
A curve of radius 161 m is banked at an angle of 12°. An 840-kg car negotiates the curve at 94 km/h without skidding. Neglect the effects of air drag and rolling friction. Find the following. (a) the normal force exerted by the pavement on the tires (b) the frictional ...
July 19, 2011

algebra
a landing airplane, moving in a straight line , passes over two points (p and q) which are 300 feet apart. when the airplane is above p, as seen from Q, its angle of elevation is 60 degress, and when above Q, as seen from p, its angle of elevation is 40 degress. at what ...
July 19, 2011

algebra
a point on one bank he finds the angle of elevation of the top of a tree on the other bank to be 60 degress. from his initial observation point he walks back 200 feet in a straight line with the tree and his first observation point and finds the angle of elevation to the top ...
July 19, 2011

Calc
A Norman window consists of a rectangle capped by a semi-circular regional. The perimeter of some particular Norman window must be 30 meters. The radius of the semi-circular region is "x" meters. The height of the rectangle is "h" meters. Find the values pf...
July 18, 2011

a landing airplane, moving in a straight line , passes over two points (p and q) which are 300 feet apart. when the airplane is above p, as seen from Q, its angle of elevation is 60 degress, and when above Q, as seen from p, its angle of elevation is 40 degress. at what ...
July 14, 2011

Chemistry
How many atoms of iron will react with an excess of sulfur to form 3.098 grams of iron (II) product? Fe + S ---> FeS (2.12x10*25) I would appreciate if an explanation would be given... I need more than just the answer. Thank you!
July 5, 2011

math
equation of the line containing the points (4, 5) and (-1, 3)
July 2, 2011

Math
Somebody repeatedly roll a fair die. If it comes up 6 he instantly wins(and stop playing); if it comes up k, for any k between 1 and 5, he he waits k minutes and then roll again. what is the expected elapsed time from when he starts rolling until he wins?
July 1, 2011

Maths
Without using tables evaluate 1+tan 60'/1-tan 60'
June 30, 2011

mathmm
How to make a sign diagram
June 28, 2011

Poetry
I’m not really good at reading poems and I need help on these two poems “Linage” by Margaret Walker and “The Courage My Mother Had” by Edna St. Vincent Millay I constantly read the poems but still don’t understand what their saying I know they ...
June 24, 2011

physics
A boy drops a stone-A, down from a cliff 480 meters high, next he throws a stone-B, 1 second later - at what initial velocity was the stone-B be thrown so as to meet the stone-A on ground at the same time? g=10 m/s2.
June 21, 2011

English
Is this poem okay? A Husband’s Kiss His kiss so soft and gentle, Sending shivers down my spine I feel the love he has for me When our lips and eyes combine His love for me is equal to mine Joining together like we are one Our two hearts are so intertwined I can’t ...
June 18, 2011

A 1.2kg block is dropped from 48cm above a spring in equilibrium. The force constant for the spring is 124N/m. Calculate the maximum compression in the spring.
June 16, 2011

Maths
What is the answer for these questions:- 1) Indefinite Integrals gcx) = (8 + 39x ^ 3) / x 2) Indefinite Integrals hcu) = sin ^2 (1/8 u) 3) Evaluate x ( 8 - 5 x ^2) dx Thank you
June 16, 2011

Precalculus
Thanks! That makes sense. One step closer to passing my final exam tomorrow!
June 15, 2011

Precalculus
The letters r and è represent polar coordinates. Write the equation using rectangular coordinates (x,y). r=1+2sinè I know that I have to use something along the lines of x=rcosè and y=rsinè, but I'm stuck when I try to figure it out. Can someone...
June 15, 2011

Geometry
Given ABCD AC=28 and AE=3x-7 find the value of x
June 15, 2011

Maths
what is the answer to this question? Indefinite Integrals fct) = 14 sin (7) + 5e ^ - 15t
June 14, 2011

Chem
how do you find the boiling temp of 2m of c6h12o6
June 12, 2011

Geometry
HELP! Two Chords AB and CD, are equidistant from the center of a circle. AB=3x+7 and CD=27-x. Solve for x and find the lengths of AB and CD
June 10, 2011

child care
thank you very much!
June 8, 2011

child care
A strategy for health promotion among infants, toddlers, and young children focuses on educational programs, physical, fitness, activities and.. A. family panning B Tabacco, alcohol,anddrug use. c. Nutrition D mental health and mental disorders. Im not sure , but I think is B...
June 8, 2011

child care
which of the following taxes must be paid only by the employer? A Federal income B State C Federal unemployment D Fica Thanks
June 7, 2011

Physics
A 1.45 mol sample of an ideal gas (γ = 1.40) is carried through the Carnot cycle described in the figure below. At point A, the pressure is 28.5 atm and the temperature is 600 K. At point C, the pressure is 1.00 atm and the temperature is 400 K. How do I get the pressure ...
June 6, 2011

language
What is the main theme in Death on the Ice by Cassie Brown?
June 5, 2011

Random Question
Posted by Alex on Saturday, June 4, 2011 at 12:55pm. Based on readings from the first 20 chapters of "Invisible Man", what does the narrator mean when he refers to himself as "invisible"? Is it because of all the situations he been in and no one really ...
June 4, 2011

Random Question
So how would you say one of the examples of the journey to solitude reflect a understanding of his own "invisibility"?
June 4, 2011

Random Question
Based on readings from the first 20 chapters of "Invisible Man", what does the narrator mean when he refers to himself as "invisible"? Is it because of all the situations he been in and no one really seeing him or his feelings? HELP PLEASE
June 4, 2011

Physics
A 5 gram bullet is fired and embeds into a 30 gram block of wood resting on a 2 m tall post. After the collision, the piece of wood lands 15 meters from the base of the post. Find the initial speed of the bullet.
June 1, 2011

Physics
A 5 gram bullet is fired and embeds into a 30 gram block of wood resting on a 2 m tall post. After the collision, the piece of wood lands 15 meters from the base of the post. Find the initial speed of the bullet.
June 1, 2011

Math
A cylindrical tank with radius 6 in. and length 12 in. is placed on its lateral face with bases perpendicular to the ground and then filled with water to a height of 9 in. When the cylinder is rotated to sit on one of its bases, the height of the water will be a+bsqrc...
May 30, 2011

math
There are 900 three-digit integers. The number of three-digit integers having at least one repeated digit is also a three-digit number. If that number is represented by abc where each letter is a digit, compute a-b+c (I came up with 252 integers so when I did the computation ...
May 28, 2011

chem
Which metal will react spontaneously with Cu^2+(aq) at 25 degree celcius? between Ag, Au, Mg, and hg?
May 28, 2011

chem
Which metal will react spontaneously with Cu^2+(aq) at 25 degree celcius?
May 28, 2011

Math
A container in the shape of a rectangle solid with the dimensions of 4 X 5 X10 is placed so that its height is 10. Water fills the container to a heaight of 6. The container is then turned so that the base dimensions are 4 X 10. Determine the height of the water in the container.
May 27, 2011

Statistics
Which of the following is NOT sensitive to extreme values? A) the range B) the standard deviation C) the interquartile range D) the coefficient of variation I pick B the standard deviation
May 27, 2011

geometry
If given 2 spheres, if the volume of the first sphere is 3/4 and the volume of the second sphere is 36, which is the relation of the second radius to the first?
May 22, 2011

computer sciece
I have a question, how do we find a Voltage, Current, Power if we use PSpice? I use the software to find all the Values but I don't know how to explain.
May 22, 2011

pre cal
what are the amplitude and period of the sinusoid y=6cosx+7sinx?
May 22, 2011

Chemistry
Stomach acid is 0.02M HCl. A 330mg antacid tablet is 41% magnesium hydroxide and 36.2% sodium Bicarbonate. What is the volume of acid that can be neutralized by one tablet?
May 21, 2011

Chemistry
Stomach acid is 0.02M HCl. A 330mg antacid tablet is 41% magnesium hydroxide and 36.2% sodium Bicarbonate. What is the volume of acid that can be neutralized by one tablet?
May 21, 2011

algebra 1
a landing airplane, moving in a straight line , passes over two points (p and q) which are 300 feet apart. when the airplane is above p, as seen from Q, its angle of elevation is 60 degress, and when above Q, as seen from p, its angle of elevation is 40 degress. at what ...
May 20, 2011

Math
Find a vector with magnitude 1 that has the same direction as the following vector U= -3i+7j
May 17, 2011

Economics
Appalachian Coal Mining believes that it can increase labor productivity and, there-fore, net revenue by reducing air pollution in its mines. It estimates that the marginal cost function for reducing pollution by installing additional capital equipment is MC 40P where P ...
May 16, 2011

Social Studies
What is the name of a Seminole home?
May 16, 2011

math
22+15= 37
May 10, 2011

chem
for my last two questions, i had Krypton as the element and 56.96 grams K3PO4. i need something to compare with
May 10, 2011

chem
A scientist wants to make a solution of potassium phosphate, K3PO4 for a lab experiment. How many grams of K3PO4 will be needed to produce 575ml of a solution that has a concentration of K+ ions of 1.4M.
May 10, 2011

chem
an empty container has a mass of 658.57g. It has a mass of 659.45g after it has been filled with nitrogen gas at a pressure of 790 torr and a temperature of 15 deg C. When the container is evacuated and refilled with a certain element at a pressure of 745 torr and a temp of 26...
May 10, 2011

chem
ethane gas, or dicarbon hexahydride, undergoes cmbustion to produce carbon dioxide gas and water vapor. A. What mass of the un named reactant is required to react with 2.2 moles of ethane? B. How amny molecules of the product with the smaller % composition of the non oxide ...
May 10, 2011

chemistry
2nd revision to the question, it is 7.62atm not 7.2atm, its now all correct on the question. sorry again Fluorine and krypton react to form binary compounds when a mixture of the two gases is heated to 500C in a nickel reaction vessel. A 100mL nickel container is filled with ...
May 10, 2011

chem
Now the numbers in the question are correct, (Fluorine = 10.10atm Krypton = 1.24atm). Please help. Fluorine and krypton react to form binary compounds when a mixture of the two gases is heated to 500C in a nickel reaction vessel. A 100mL nickel container is filled with fluorin...
May 10, 2011

chem
don't have the answer but to help those trying to help, it should be 10.10 atm for Fluorine, and 1.24 atm for Krypton.
May 9, 2011

Trigonometry
How would you find the both primary solutions to 3cos(2x) = 2.5
May 7, 2011

psychology
May 6, 2011

psychology
May 6, 2011

math
Find the general term: 4/3, 7/7, 10/11, 13/15,...
May 5, 2011