Monday

June 27, 2016
Total # Posts: 2,785

**Chemistry**

Help with any of these: 21. Aluminium sulphate is often used by gardeners to acidify soil and can be produced by the reaction 2Al(OH)3(aq) + 3 H2SO4(aq) à Al2(SO4)3(aq) + 6 H2O(l) The volume of 0.275 mol/L H2SO4(aq) needed to react completely with 112...
*September 9, 2012*

**Physics**

An attacker at the base of a castle wall 3.82 m high throws a rock straight up with speed 7.10 m/s from a height of 1.45 m above the ground. (a) Will the rock reach the top of the wall? __yes __no (b) If so, what is its speed at the top? If not, what initial speed must it have...
*September 8, 2012*

**Help On Math**

Thanks
*September 8, 2012*

**Help On Math**

A movie theater has fixed costs of $5,500 per day and variable costs averaging $2 per customer. The theater charges $7 per ticket. How many customers per day does the theater need in order to make a profit? Give the smallest possible value. The theater makes a profit when it ...
*September 8, 2012*

**phys**

A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 3.30 m/s. The car is a distance d away. The bear is 32.9 m behind the tourist and running at 4.92 m/s. The tourist reaches the car safely. What is the maximum possible value for d?
*September 6, 2012*

**phys**

A pellet gun is fired straight downward from the edge of a cliff that is 28.5 m above the ground. The pellet strikes the ground with a speed of 26.1 m/s. How far above the cliff edge would the pellet have gone had the gun been fired straight upward?
*September 6, 2012*

**phys**

A woman on a bridge 84.7 m high sees a raft floating at a constant speed on the river below. She drops a stone from rest in an attempt to hit the raft. The stone is released when the raft has 8.02 m more to travel before passing under the bridge. The stone hits the water 4.86 ...
*September 6, 2012*

**Math**

I need to solve this set of differential equations {y'+(t/2)1, y(0)=1} and then find the limiting value as t approaches infinity. I'm not sure where to start. I found the answer to the differential equation to be: y(t)=e^-t^2/4[e^(r^2/4)dr +Ce^(-t^2/4)where the [ sign ...
*September 6, 2012*

**physics**

A heavy piece of equipment(85kg) is being moved by elevator between floors in a building. Two identical small cranes are used. A cable connecting each crane to a mounting hook on the top of the piece of equipment.The cable from one crane is at an angle of 22 degree below the ...
*September 5, 2012*

**DT**

For my DT homework I need to do a health and safety poster on a Pillar Drill. I need to find health and safety facts on a Pillar Drill. Please can you help me. Thanks
*September 4, 2012*

**physics**

You are driving down the road at a constant speed. another car going a bit faster catches up with you and passes you. draw a position graph for both vehicles on the same set of axes and note the point on the graph where the other vehicles passes you. if you have been passed by...
*September 4, 2012*

**physics**

A viking sails from his home port and travels east at 15km/hr.after 10 hours, the wind change and he is blown south west at 20km/hr for six hours.at his point wind drops, the ship is becalmed and doesnot move for the next ten hours.becoming tired of waiting,the viking order ...
*September 4, 2012*

**physics**

A landing craft of mass 12000 kg prepare itself for moon landing. when at a vertical distance 160m above the moons surface its downward velocity is 15 m/s. a retrorocket is fired to give the craft an upward thrust to slow its speed to zero as it meet the surface.calculate the ...
*September 4, 2012*

**science**

A simple model for a person running a 100m race is to assume the sprinter runs with constant acceleration until reaching top speed, and then maintains that speed through the finish line. If a sprinter reaches their top speed of 11.2ms-1 in 2.15s, what will be their total time?
*September 4, 2012*

**chemistry**

Sulfuric acid (H2SO4) is prepared commercially from elemental sulfur using the contact process. In a typical sequence of reactions, the sulfur is ﬁrst burned: S + O2 → SO2 , then it is converted to SO3 using a catalyst: 2 SO2 + O2 → 2 SO3 . The resulting SO3...
*September 2, 2012*

**chemistry**

A 12.8 g sample of iron ore is treated as follows. The iron in the sample is all converted by a series of chemical reactions to Fe2O3. The mass of Fe2O3 is measured to be 21.3 g. What was the mass of iron in the sample of ore? Answer in units of g
*September 2, 2012*

**algebra**

how do i explain how to write 20 miles/4 hours as a unit rate?
*August 30, 2012*

**ap chemistry**

name five organic compounds that melt between -40 degrees and -49 degrees celsius
*August 26, 2012*

**Algebra**

Thank You Reiny i see what you did there :) i was confused on some of the things but i understand how to do that stuff now! Thanks Again!, Emily
*August 22, 2012*

**Algebra**

BTW!!! I need it explained on like how you figured it out because i have another ? like it and i want to try and do that one on my own!!! THX! ;)
*August 22, 2012*

**Algebra**

I need help with this like really badly sooo yeahhhh:) here it is: Hugo withdrew some money from his bank account. He spent one third of the money for gasoline. Then he spent half of what was left for a haircut. He bought lunch for $6.55. When he got home,he had $13.45 left. ...
*August 22, 2012*

**health**

Teachers are there to help, not provide answers to kids. She's handing them the necessary tools to get the answer and they are still choosing to be lazy and guess. Stop judging a teacher for being impatient. Blame a parent for not disciplining their child
*August 14, 2012*

**Physics**

20/9
*August 7, 2012*

**health!**

the answer is C
*August 3, 2012*

**programming**

Given a = 5, b=1, x=10, and y =5, create aprogram that outputs the result of the formula f = (a b)(x y) using a single printf() function. B> Create a program that uses the same formula above to output the result; this time however, prompt the user for the values a, b, x, ...
*July 24, 2012*

**Math **

1.) A security code has seven characters. Each code begins with two digits, then two letters, and finally three digits. the number of distinct security codes possible if repetition is allowed? 2.) How many ten digit phone numbers are possible if a number may not begin with a 0...
*July 16, 2012*

**Physics**

For part c, it says regarding the common velocity Vf isn't that different than Vcm?
*July 10, 2012*

**Physics**

I figured out a and b, but I can't seem to figure out C.
*July 10, 2012*

**Physics**

Car 1 has a mass of m1 = 65 103 kg and moves at a velocity of v01 = +0.76 m/s. Car 2, with a mass of m2 = 92 103 kg and a velocity of v02 = +1.5 m/s, overtakes car 1 and couples to it. Neglect the effects of friction in your answer. (a) Determine the velocity of their center ...
*July 10, 2012*

**Physics**

Two forces, 1 and 2, act on the 5.00 kg block shown in the drawing. The magnitudes of the forces are F1 = 58.0 N and F2 = 26.5 N. What is the horizontal acceleration (magnitude and direction) of the block?
*June 27, 2012*

**Physics**

The 1994 Winter Olympics included the aerials competition in skiing. In this event skiers speed down a ramp that slopes sharply upward at the end. The sharp upward slope launches them into the air, where they perform acrobatic maneuvers. In the women's competition, the end...
*June 27, 2012*

**Physics**

In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 36 m/s (around 80 mi/h) in a time of 5.5 s. The mass of the car and riders is 4900 kg. Find the average net force exerted on the car and riders by the ...
*June 26, 2012*

**Physics**

A person with a black belt in karate has a fist that has a mass of 0.70 kg. Starting from rest, this fist attains a velocity of 6.9 m/s in 0.15 s. What is the magnitude of the average net force applied to the fist to achieve this level of performance?
*June 26, 2012*

**Physics**

Could someone explain how to do this?
*June 22, 2012*

**Physics!!!**

A cube of wood and a cube of concrete, each 0.17 m on a side, are placed side by side. One of the long faces of the rectangular prism formed by the two cubes is held at 17°C, and the opposite long face is held at 32°C. What is the total rate of heat transfer through ...
*June 22, 2012*

**Physics**

A cube of wood and a cube of concrete, each 0.17 m on a side, are placed side by side. One of the long faces of the rectangular prism formed by the two cubes is held at 17°C, and the opposite long face is held at 32°C. What is the total rate of heat transfer through ...
*June 21, 2012*

**math**

diving 12 and56
*June 16, 2012*

**Geometry**

The math club of Ritzy High designed a pennant for the school yacht. The pennant was in the shape of an isosceles triangle. Two points, P and Q, are located so that AC= PQ= QB. Find the measure of angle B.
*June 9, 2012*

**Physics**

How are you getting -44 mph for the final velocity?
*June 6, 2012*

**Physics**

How fast would a 9-g fly have to be traveling to slow a 1790-kg car traveling at 58 mph by 4 mph if the fly hit the car in a totally inelastic head-on collision?
*June 6, 2012*

**math**

create a situation that can be modelled by this linear system, then write a related problem. 10x + 5y = 850 x - y = 10
*June 3, 2012*

**math**

26 math words
*May 31, 2012*

**math**

26 math words
*May 31, 2012*

**physics**

A spherical mirror has a focal length of −0.59 m. An object of height 0.045 m is located 0.42 m in front of the mirror. What is the height (including its sign) of the object’s image?
*May 29, 2012*

**Precalculus**

What are the exact values for which tan t = -(sqrt3)
*May 23, 2012*

**chemistry**

3CaCO3+2FePO4-->Ca3(PO4)2+Fe2(CO3)3 We start with 100g. of calcium carbonate and 45g. iron (III) phosphate. What is the maximum amount of Ca3(PO4)2 and Fe2(CO3)3 ??
*May 14, 2012*

**Physics**

A 1.4 kg mass is attached to a spring with a force constant of 56 N/m. If the mass is released with a speed of 0.26 m/s at a distance of 8.6 cm from the equilibrium position of the spring, what is its speed when it is halfway to the equilibrium position?
*May 14, 2012*

**English**

She TRIED and she was looking to see if her answers were correct, which they were not so someone gave her the right answers, she learned from this. Your ignorance was not needed nor is it wanted. Btw getting an education is succeeding and learning, which is what this was! ...
*May 13, 2012*

**Chemistry**

A bond between two sugar molecules is formed by which of the following types of reactions? oxidation-reduction condensation single-replacement double-replacement
*May 10, 2012*

**Chemistry**

What can you say about the energy spread of the radiation emitted by an atomic gas?
*May 8, 2012*

**Chemistry**

Based on the spectrum of the fluorescent lamp, what is the main difference between the radiation emitted by a heated solid (filament) and the radiation emitted by an atomic gas (mercury gas in the fluorescent tube)?
*May 8, 2012*

**Chemistry**

Thank you SO much!
*May 8, 2012*

**Chemistry**

1. Describe the relationship between the color change of the filament with temperature, and the colors in the observed spectrum of white light. 2. Order the colors of the rainbow according to the amount of energy needed to produce them, from lowest to highest.
*May 8, 2012*

**Calc III**

Find the position vector of a particle that has the given acceleration and the specified initial velocity and position. a(t)= 56t i + sin(t) j + cos(2t) k v(0)= i r(0)= j I need help finding r(t) Thanks so much for your help!!
*May 4, 2012*

**visual and performing arts**

Explain why the Chartres Cathedral both is and isn't an example of the "High Gothic" style. Be sure to reference specific pieces of art in your response.
*May 3, 2012*

**visual and performing arts**

well i think its pythagoros or socrates but im not sure.
*May 3, 2012*

**visual and performing arts**

From what Greek philosopher did Abbot Suger draw inspiration? .Aristotle .Socrates .Pythagoros .Pseudo-Dyonysius
*May 3, 2012*

**performing and visual arts**

im not at all sure about this one.
*May 3, 2012*

**performing and visual arts**

What is another name for Gherardo Starnina? .Master of Bambino Vespo .Gentile da Fabriano .Duccio Buoninsegna .Giotto Bondone
*May 3, 2012*

**Chemistry**

A 55.0-mg sample of Al(OH)3 is reacted with 0.200M HCl. How many milliters of the acid are needed to neutralize the Al(OH)3.
*May 1, 2012*

**Chemistry**

What is the molarity of a sodium hydroxide solution if 38 mL of the solution is titrated to the end point with 14 mL of 0.75M sulfuric acid?
*May 1, 2012*

**Chemistry**

What is the molarity of a sodium hydroxide solution if 38 mL of the solution is titrated to the end point with 14 mL of 0.75M sulfuric acid?
*May 1, 2012*

**statistics**

if the null hypothesis is that the mean is 3218, the alternative hypothesis is that the mean > 3228, and the sample mean is x= 3342, the sample standard deviation is s=287, the sample size is n= 42, and α= 0.01 a. calculate the z test statistic. b. what is the p-value...
*April 29, 2012*

**statistics**

do you want to own your won candy store? start up costs (units in 1,000) for a random sample of candy stores are: (95, 173, 129, 95, 75, 94, 116, 100, 85) Use an 80% confidence interval to test the null hypothesis that the mean start up cost is 118. Justify answer.
*April 29, 2012*

**statistics**

sorry, the question is above this link
*April 29, 2012*

**book report**

can someone show me how a third grade bokreport layout is done
*April 28, 2012*

**Consumer Math**

Find the annual amount of FICA at a 7.51% rate by computing his annual salary. Sam Takagi Weekly salary: $435.16 Not self-employed Find the annual amount of FICA by computing his annual salary. $169,938.68 $16,993.87 $1,699.39 2. Find the annual amount of FICA at a 7.51% rate...
*April 27, 2012*

**Chemistry**

A sample of ammonium salt (NH4X) having a mass of 1.618g was heated with NaOH and the liberated ammonia was reacted with 50.00 of .6230 mol/L HCl. The excess acid required 1.50 mL of .6115 mol/L NaOH in titration. What is the formula of the salt?
*April 25, 2012*

**College Chemistry**

I need help with this question!! a sample of pure KHP weighing .8097g dissolved in water and titrated with 40.25 mL of NaOH solution. The same NaOH solution was used to titrate a solution of a weak diprotic acid H2X. A sample of 0.18694g of the weak acid was first dissolved in...
*April 25, 2012*

**Visual & Performing Arts - Semester 1 Class**

unity
*April 24, 2012*

**Visual & Performing Arts - Semester 1 Class**

When all the portions of an artwork are combined and seem to function collaboratively, the composition is said to have?
*April 24, 2012*

**us history**

Who did the Santa Fe Trail get estblaished for?
*April 23, 2012*

**physics @ elena**

I saw that u aready did this, but when I calcuated everything my answers were still wrong
*April 22, 2012*

**physics @ elena**

can you please help me with this one At serve, a tennis player aims to hit the ball horizontally. part a)What minimum speed is required for the ball to clear the 0.90m--high net about 15.0m from the server if the ball is "launched" from a height of 2.50m ? part b)...
*April 22, 2012*

**physics**

An athlete executing a long jump leaves the ground at a 28.0 angle and lands 7.60m away. part a)What was the takeoff speed? part b) If this speed were increased by just 8.0 % , how much longer would the jump be? i got for part a)9.48 m/s but i need help with part b
*April 22, 2012*

**physics. HELP PLEASE !**

An athlete executing a long jump leaves the ground at a 28.0 angle and lands 7.60m away. part a)What was the takeoff speed? part b) If this speed were increased by just 8.0 % , how much longer would the jump be? i got for part a)9.48 m/s but i need help with part b
*April 22, 2012*

**Chemistry**

Which pair of compounds will form a solution? A) Benzene (C6H6) and Hexane (C6H14) B) Na2SO4 and Benzene C) NaCl and Hexane
*April 20, 2012*

**Economics**

Staples. They are likely to remain fixed, thus having an inelastic supply.
*April 19, 2012*

**Math 10 Linear Equations**

I got the same except for the last one. .5x=23 x=46
*April 19, 2012*

**Math 10 Linear Equations**

Kevin opened a bank account and plans to deposit $200 each month. Each time he makes a deposit, his parents have agreed to add 50% of the amount the family collects for returning cans and bottles. a) Write an equation that will show his monthly amount when the family collects ...
*April 19, 2012*

**Religion**

Youtube - The Maccabeats - Candlelight - Hanukkah Please watch the video above and tell me a piece of Catholic wisdom about a feast day or holiday in the Catholic church. Please please please please
*April 14, 2012*

**algebra2**

simplify fourth root sqrt 32x^11y^15/fourth root sqrt 2x^3y^-2
*April 14, 2012*

**cochise**

How many kilocal are required to increase the temperature of 15.6 g of iron from 122 °C to 355 °C? The specific heat of iron is 0.450 J/g °C
*April 13, 2012*

**Economics**

It's B. Sorry,
*April 12, 2012*

**Economics**

it's D.
*April 12, 2012*

**health**

Children and adolescents are considered to be reflected in which age group? A. 6-17 years old B. 3-17 years old C. 5-17 years old D. 10-17 years old
*April 11, 2012*

**chemistry**

The decomposition of potassium chlorate, KClO3, gives oxygen gas and solid potassium chloride. How many grams of KClO3 are needed to produce 5.00 L of Oxygen gas at STP? Suppose that the reaction described above produces 4.80 L of O2 in the laboratory. What is the percent yield?
*April 10, 2012*

**Physics**

in an impulse/ change in momentum problem where mv(final)-mv(initial)=Ft if the initial velocity is zero can i cancel out the masses?
*April 10, 2012*

**Chemistry**

how many joules of heat are given off when 5.0 grams of water cool from 75 degrees celsius to 25 degrees celsius? ( specific heat of water = 4.18 jg degrees celsius)
*April 9, 2012*

**Math**

write the particular equation of a quartic function that could, according to Descartes Rule of Signs have four positive zeros.
*April 9, 2012*

**physics**

You are trying to raise a bicycle wheel of mass m and radius R up over a curb of height h. To do this you apply a horizontal force F. What is the smallest magnitude of the force F that will succeed in raising the wheel onto the curb when the force is applied (a) at the center ...
*April 8, 2012*

**chemistry**

How does Le Chatelier's principle explain the result you obtained after the addition of NaOH?
*April 7, 2012*

**healthcare**

treat them as if they were someone who is the same age as you.
*April 7, 2012*

**Chemistry**

when 0.20 mole HF is dissolved in water to a volume of 1.00 L, 5.8% of the HF dissociates to form F- (aq). What is the equilibrium constant for the reaction ? HF(aq) +H2O(l) ------ F- (aq) +H3O+ (aq)
*April 5, 2012*

**trig**

cos(sin^-1 x)=sq rt(1-x^2) prove the identity
*April 2, 2012*

**trig**

Give the following for the function: y=2+cos(5x+3.14 Amplitude: Period: Phase Shift:
*April 1, 2012*

**Trig**

A 7.25 inch circular saw blade rotates at 5200 revolutions per minute. a) Find the angular speed of the saw blade in radians per minute. b) Find the linear speed in feet per minute of one of the 24 cutting teeth as they contact the wood being cut.
*April 1, 2012*

**MATH HELP**

At Jefferson College 15% of all students participate in athletics. If a class consists of 33 randomly selected students, how many of them would you expect to participate in athletics?
*April 1, 2012*

**Trig**

A carousel with a 50-foot diameter makes 4 revolutions per minute. a) Find the angular speed of the carousel in radians per minute. b) Find the linear speed in feet per minute of the platform rim of the carousel.
*April 1, 2012*

**Statistics**

At the Starlight Jewelry store, the customer preferences for wedding bands is 60% yellow gold, 29% white gold and 11% platinum. If 15 customers are randomly selected, what is the probability that more than 10 of them choose yellow gold wedding bands?
*April 1, 2012*