# Posts by ahmed

Total # Posts: 127

**statistics**

A random variable has aprobability function p(x)=kx; x=1,2,3,4,5.find the value of k, p(x>=3),compute mean and variance of x.

*January 15, 2017*

**PHYSICAL CHMISTRY**

A sample of methane gas of mass 35 g at 250 K and 12.5 atm expands isothermally until its pressure is 1.5 atm. Determine the change in entropy of the gas.

*December 20, 2016*

**Math**

Consider ?C such that sin C = 7/25 a) What are the possible quadrants in which ?C may lie? b) If you know that cos C is negative, how does your answer to part a) change? c) Sketch a diagram to represent ?C in standard position, given that the condition in part b) is true. d) ...

*November 23, 2016*

**Physical**

A toy rocket is launched vertically from ground level (y = 0 m), at time t = 0.0 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 73 m and acquired a velocity of The rocket continues to ...

*November 1, 2016*

**Geography**

Name three key reasons for migration

*October 25, 2016*

**geography**

I need to compare a coastal, mountainous or desert area from Australia to a counterpart in a developing country then discuss their management, sustainability, tourism applications etc. I need assistance in choosing countries as I am having trouble finding relevant information.

*October 4, 2016*

**Math**

Charlotte divided a whole pizza into 4 pieces . One piece formed a straight angle. One piece formed a right angle . Two pieces formed acute angles with the same degree measure

*February 18, 2016*

**phyis**

a 5 gram rubber ball is released from a height of 7 meter above flat surface on the moon. gravitational acceleration on the moon is 1.62 meters per second squared. assume that no energy is lost from frictional drag. what is the velocity, in units of meters per second, of the ...

*February 17, 2016*

**chemistry**

how to draw bicyclo 3.1.1 heptane ? I need steps to draw any of this compounds in exam ?

*January 21, 2016*

**chemistry**

which of the following has highest binding energy (nuclear chemistry) Fe-56 , O-16 , H-3 , U-235 and explain why

*January 15, 2016*

**chemistry**

nuclear

*January 15, 2016*

**chemistry**

why iron 56 has highest binding energy than oxygen 16 , although oxygen 16 more stable than iron 56 ???

*January 15, 2016*

**chemistry**

the half-life of tritium is 12.26 y what would be the rate of decay of tritium atoms per second in 1.00 L of hydrogen gas at STP containing 0.15% tritium atoms ?

*January 15, 2016*

**Math**

box 569 divided by 6 is 400 what digit show be in the box?

*January 14, 2016*

**chemistry**

the half-life of tritium is 12.26 y what would be the rate of decay of tritium atoms per second in 1.00 L of hydrogen gas at STP containing 0.15% tritium atoms ?

*January 14, 2016*

**chemistry**

What would be the mass ratio of Pb-208/Th-232 in a meteorite that is approximately 4.5 × 10^9 years old? The half-life of Th-232 is 1.39 x 10^10 years i'm used t= 3.32 t(1/2) logNo/N but the result is not correct !?

*January 14, 2016*

**chemistry**

isotope A require 12h for its decay rate to fall to 1/64 of its intial value . isotope B has half-life = 1.5 half life of A how long does it take for decay rate of B fall to 1/32 of its initial value ?

*January 13, 2016*

**basic mathematics**

ii) A box contains 10 white, 7 black and 3 green balls. 2 balls are drawn at random. Find out the probability that: a) both are white b) one is white and another is green c) one is black and another is green

*December 29, 2015*

**physics**

A soccer ball is kicked from the ground with initial speed 17 m/s. at angle(a 20 Find a) The horizontal distance that the ball travels after 4s? b) The speed of the ball at the highest point?

*December 26, 2015*

**Grover Cleveland high school**

I don't know the answer

*December 8, 2015*

**Grover Cleveland high school**

Ramy jumped from the window from the height of 400 feet. His speed of feeling was 10 feet. second write a functions to represent the situation.explain the answer please

*December 8, 2015*

**Physics 12 college preparation**

Find the work done by a traveller carrying a suitcase of mass 8.2 kg by pulling up on it when walking forward for a distance of 120 m . Explain your reasoning

*November 20, 2015*

**physics**

On a plot of position x versus time t for an object’s motion, what corresponds to the object’s average velocity between instant t1 and instant t2? (a) intercept of the plot on the horizontal axis (b) intercept of the plot on the vertical axis (c) slope of a line ...

*October 9, 2015*

**mahamuud xarbi**

a motorboat accelerates uniformly from a velocity of 6.5m/s the west to velocity of 1.5m/s to the west if its acceleration was 2.7m/s^2 to the east how for did it travel daring the acceleration

*September 8, 2015*

**math**

Bob does 2/7 of a book in 1 hour.how long will he take to do the remaining work?

*June 16, 2015*

**physics**

the positive point charges + q are placed at three corners of a square , and a negative point charge -Q is placed at the fourth , corner. the side of the square is L. calculate the net electric force that positive charges exert on the negative charge

*March 19, 2015*

**physics**

A 4.40kg bucket of water is accelerated upward by a cord of negligible mass whose breaking strength is 74.0N

*March 2, 2015*

**physics**

A block of mass m slides down a frictionless incline as The block is released from height h above the bottom of the circular loop. (a) Find the force exerted on the block by the inclined track at point A. (Hint: Consider the Newton’s 2nd law in the radial direction and ...

*January 8, 2015*

**Math**

50+225

*November 30, 2014*

**electromagnetic just put the rule**

In a certain material for which µ = 6.5 o , H = 10ax + 25ay - 40az A/m Find (a) The magnetic susceptibility xm of the material (b) The magnetic flux density (c) The magnetization, (d) The magnetic energy density I just want the rule of them

*October 31, 2014*

**Materials Science**

-8.4 *10^-5

*October 1, 2014*

**Physics**

A force F acts to the right on a 4.81 kg block. A 2.53 kg block is stacked on top of the 4.81 kg block and can slide on it with a coefficient of friction of 0.2 between the blocks. The table has a coefficient of friction of 0.23. The acceleration of gravity is 9.8 m/s 2 . The ...

*September 28, 2014*

**math**

a quart is approximately sixty cubic inches. a cubic feet of water weighs approximately sixty pounds. therefore, a quart of water weighs, approximately

*August 7, 2014*

**mechanics**

A diver’s take - off velocity is 5 m/s at an angle of 15º to the horizontal during a dive. His centre of gravity is 0.4 m above the pool deck level at take - off (point A, Figure Q1(a)) and is 0 m above deck level when he enters the water (point D, Figure Q1(a)). How...

*August 1, 2014*

**maths**

She adds the to number together and divides the result by 2her answer is 44 one of EMilys numbers is 12what is Emilys other number?

*June 15, 2014*

**كيمياء**

q// calculate the concentration of Potassium ion in grams per liter after mixing 100mL of 0.250M KCL and 200 mL OF 0.100 M k2SO4?

*June 5, 2014*

**UOS**

A parallel plate capacitor has a capacitance of 7.0mF when filled with a dielectric. The area of each plate is 1.5m2 and the separation between the plates is 1.0x10-5m. What is the dielectric constant of the dielectric?

*April 26, 2014*

**Calculus Help Please!!! Found the answer**

(-0.383,0.516)

*April 4, 2014*

**Chemistry Help Please!!!**

Find Net Ionic equation for hydrolysis , Expression for equilibrium constant (Ka or Kb) and Value of (Ka or Kb) Net Ionic equations I've got NaC2H3O2 == CH3COO^-+H2O -->CH3COOH+OH^- Na2CO3 ==== CO3 + 2H2O → H2CO3 + 2-OH Kb = [H2CO3] [-OH]2 / [CO3]. Kb = 1/Ka1Ka2...

*April 3, 2014*

**Calculus Help Please**

the linear app. appears to be best for the function ___f___ since it is closer to ___f__ for a larger domain than it is to _g and h____ . the app. looks worst for ___h__ since _h____ moves away from L faster than __f and g___ do.

*April 2, 2014*

**Calculus Help Please Check!!!**

Lf(x)= 1-2x Lg(x)= 1-2x Lh(x)= 1-2x the linear app. appears to be best for the function ___f___ since it is closer to _____ for a larger domain than it is to _____ . the app. looks worst for ___h__ since _____ moves away from L faster than _____ do. i couldn't figure out ...

*April 2, 2014*

**Calculus Help Please**

let f(x)=(x-1)^2, g(x)=e^(-2x), and h(x)=1+ ln(1-2x) find linearization of f, g, and h at a=0 Lf(x)= Lg(x)= Lh(x)= graph f,g, and h, and their linear app. For which function is the linear app. best? for which is the worst? explain. the linear app. appears to be best for the ...

*April 2, 2014*

**physics**

A gry is an old English measure for length, defined as 1/10 of a line, where line is another old English measure for length, defined as 1/12 inch. A common measure for length in the publishing business is a point, defined as 1/72 inch. What is an area of 0.42 gry2 in points ...

*March 23, 2014*

**physics**

If the average time from one on state to the next one on the first photogate is 0.005 seconds, what is the speed of the cart at this point (LEAVE OUT the units of m/s)?

*March 20, 2014*

**Numerical Analysis**

can anyone just tell which rule i can use

*March 16, 2014*

**Numerical Analysis**

Use appropriate Lagrange interpolating polynomials of degrees one, two, and three to approximate each of the following: a. f(8.4) if f(8.1) = 16.94410, f(8.3) = 17.56492, f(8.6) = 18.50515, f(8.7) = 18.8209 help pls

*March 16, 2014*

**marine physics**

If the sea level rises by 20 cm from west to east , across the Red sea, a distance of 250 km at 20 N, what is the average speed and direction of the current

*February 18, 2014*

**Engineering**

A 10.0 Kg block is released from point A in the figure below. The block travels along a smooth frictionless track. It makes a collision with stationary 10 kg ball. The ball moves forward with speed of 2 m/s. a) What is the speed of the block at point C? b) What is the velocity...

*June 7, 2013*

**marine**

on perfectly smooth and frictionless hockey field at 20n , how slowly a puck be driven to perform an inertial circle of diameter equal to the field width 26m

*March 21, 2013*

**math**

If i earned $20 in January,$5 in February and $20 in March! What is the mean (average) amount of money earned for these 3 months? what is the answer and can you explain the question to me please

*March 13, 2013*

**mechanics**

B 7.0x103 Dear who are you??? mail me on

*February 24, 2013*

**physical**

An asteroid in an elliptical orbit about the sun travels at 3.9 106 m/s at perihelion (the point of closest approach) at a distance of 3.7 108 km from the sun. How fast is it traveling at aphelion (the most distant point), which is 8.6 108 km from the sun?

*January 24, 2013*

**World history**

This relationship has started some kind of wars, because It had sour between the people doing what they are supposed to do when they don't have any choice. In this war they for they armies to surrender or suffer death in the art of war.

*January 14, 2013*

**answer**

for number 1 its D for number 2 its B for number 3 its B for number 4 its C

*November 9, 2012*

**engineering**

can you give us the solution

*October 17, 2012*

**COMPUTER SCIENCE JAVA**

Assignment problems: Write Java programs for each of the following. 1. Students in a university class are being organized into groups of three for an upcoming research project. To model this situation: a. Write a Student class that stores the name, email address and phone ...

*October 15, 2012*

**COMPUTER SCIENCE JAVA**

Assignment problems: Write Java programs for each of the following. 1. Students in a university class are being organized into groups of three for an upcoming research project. To model this situation: a. Write a Student class that stores the name, email address and phone ...

*October 15, 2012*

**us history**

Which was not one of the causes of the Great Depression? (Points : 5) excessive income taxes speculative stock purchases risky banking practices severe drought

*May 12, 2012*

**math**

The graph of the range of scores for the games is shown below. The inequality for the graph can be expressed as 32 ≤ r ≤ m where r is the minimum range of the scores in any of the games and m is the maximum range. What is the value of m?

*April 15, 2012*

**math**

The javelin event is held on the field inside the track. This field is a rectangle measuring 100 meters by 64 meters, with a semicircle at each end. Early modern Olympic javelins were designed so well that javelin throwers could throw them beyond the field and onto the track. ...

*April 15, 2012*

**Physics grade 12**

F=q•v•B•siná, sin á =1. mv^2/R = q•v•B, R= mv/qB. The period is T =2•ð•R/v = 2•ð•m/q•B. For á-particle T = 2•ð•4m(p)/2•e•B. T/2 = 2•ð• m(p)/ e•B

*April 5, 2012*

**Ss**

The influence of oil in Saudi Arabia has effected Saudi Arabia. For example they used oil accounts for more than 90% of exports and nearly 75% of government revenues, facilitating the creation of a welfare state. Another example is that the government is attempting to ...

*April 3, 2012*

**math**

37.5

*March 25, 2012*

**mpf**

how long will it take for $ 500 to amount $700 of interested at $8% compounded quarterly?

*March 14, 2012*

**Physics**

vector a points in the negative x direction and has a magnitude of 22 units . The vector B points in the positive y direction a. Find the magnitude of B if A+B has a magnitude of 37 units b. sketch A and B

*March 13, 2012*

**Algebra**

3mn+6m + pn+2p and am not sure

*February 29, 2012*

**math**

Put g in f so 5(3x-4)+2 15x-20+2 =15x-18

*February 29, 2012*

**calculus**

determine the intervals where f(x) = ln(6x-24) is continuous

*February 29, 2012*

**Math**

19->1]^.>~>|\352564

*February 12, 2012*

**Math**

How do you substitute a proportion

*December 11, 2011*

**math**

What amounts are to be adjusted?

*December 4, 2011*

**chemistry**

One of the steps in the Ostwald process for the production of nitric acid involves oxidation of ammonia. 4NH3 (aq) + 5O2 (g) <---> 4NO (g) + 6H2O (g), Delta H= -905kJ a) State the reaction conditions that favour the production of nitrogen monoxide. b) A rhodium/platinum ...

*December 4, 2011*

**physics**

A boat’s speed in still water is vBW = 1.85 m/s. If the boat is to travel directly across a river whose current has speed vWS = 1.20 m/s, at what upstream angle must the boat head?

*November 15, 2011*

**candle**

The flywheel of a prototype car engine is under test. The angular position θ of the flywheel is given by θ = (3.0rad/s3)t3 and the diameter of the flywheel is 36cm. (a)Find the distance that a particle on the rim moves during that time interval. (b) Find the angle &#...

*November 4, 2011*

**Math**

do the following moves in a coordinate system: start at the origin facing in the positive y direction and move 1 unit. For each subsequent move, it is to turn 90 degrees clockwise and go forward 1 unit farther than it went in the previous move. What is the sum of the ...

*October 12, 2011*

**plz help me in physics**

A ship leaves the island of Guam and sails a distance 295km at an angle 35.0 north of west. a:In which direction must it now head so that its resultant displacement will be 100km directly east of Guam? (Express your answer as an angle measured south of east) b:How far must it ...

*October 5, 2011*

**physics**

the unit of the distance is km but plz can you give me the answer directly

*October 3, 2011*

**physics**

A ship leaves the island of Guam and sails a distance 295 at an angle 35.0 north of west. How far must it sail so that its resultant displacement will be 100 directly east of Guam?

*October 3, 2011*

**PHYSICS**

Two vectors and have magnitude A = 2.90 and B= 3.00. Their vector product is A X B= -4.91 + 2.08. What is the angle between A and B?

*October 3, 2011*

**physics**

thnx very much its correct

*October 1, 2011*

**physics**

You are camping with two friends, Joe and Karl. Since all three of you like your privacy, you don't pitch your tents close together. Joe's tent is 16.0 from yours, in the direction 26.0 north of east. Karl's tent is 29.0 from yours, in the direction 35.0 south of ...

*October 1, 2011*

**CHEMISTRY**

WHAT ARE FACTOR FAVOURING THE FORMATION OF A COVALENT BOND SHORT NOTE?

*September 28, 2011*

**stat**

Weinberger and Spotts compare the use of humor in television ads in the United States and the United Kingdom. Suppose that independent random samples of television ads are taken in the two countries. A random of 400 television ads in the United Kingdom reveals that 142 use ...

*July 24, 2011*

**english**

please,help me find mistake in the following sentence she is very hardworking so not very imaginative

*June 11, 2011*

**tax accounting**

Congress recently enacted an non refundable credit based on the cost of the qualifying alcohol and drug abuse counseling programs provided by and corporate employer to its employees . The credit is limited to 50 % of the total cost of the program .if a corporation elects the ...

*June 9, 2011*

**social studies**

Ways to be safe in class

*April 26, 2011*

**math**

1404.37

*February 24, 2011*

**chemistry**

the solution contain 6 grams of caustic soda dissolved per dm.find the percentage impurity

*November 15, 2010*

**Social St**

What kind of indians already lived in colonial New York?

*November 6, 2010*

**chemistry**

nearest star distance of 4.3 light years proxima centauri is the nearest star to our solar system. what is the distance to proxima centauri kilometers? the speed of light in space is 2.998 x10^8 m/s.

*October 24, 2010*

**Science**

inherited

*October 20, 2010*

**3rd grade**

yes,beacause 7*2=14.

*October 20, 2010*

**Writing**

It's NewYork,Jacksin Heights

*October 20, 2010*

**Writing**

I have to write how Is the City Not Safe? Is there any other things why it is not safe

*October 20, 2010*

**Writing**

If there is not enoufh police patroling in the city what would happen to us citizens?

*October 20, 2010*

**PHYSICS ---HELP!**

the answer is = 1

*October 6, 2010*

**science**

what is the another name for vitamin c

*October 4, 2010*

**science**

i don't no

*September 20, 2010*