Tuesday

April 21, 2015

April 21, 2015

Total # Posts: 6,581

**physics**

When archer pulls an arrow back in his bow.He is storing potential energy in his bow What avg force must the archer exert if he pulls the string back a distance of 30 cm?
*November 15, 2012*

**english(quotes)**

The identity you stand up for can enslave you and close you to the rest of the world. -Murathan Mungan What does this quote mean?
*November 15, 2012*

**Algebra II - Word Problem**

If a car is traveling downhill at 45 miles per hour on dry pavement, then the braking distance B is B = 45/(0.4+m), where m<0 is the slope of the road. Find the slope of the road if the braking distance is 125 feet.
*November 15, 2012*

**Algebra II - Word Problem**

I'm guessing it's 48 seconds, but not sure... Thanks!
*November 15, 2012*

**Algebra II - Word Problem**

A convenience store clerk can wait on 6 customers per minute. If customers arrive at an average rate of x people per minute, the time T spent in line is T = 1/(6-x), where 0<x<6 Find the waiting time if an average of 4.75 people arrive each minute.
*November 15, 2012*

**physics**

NEVERMIND I GOT IT
*November 15, 2012*

**physics**

A body of mass m is attracted to a 11 kg mass 31.2cm away with a force magnitude of 6.42 x 10^-8 Find m? I am having trouble with the algebra getting m by it self just show me the steps if you can
*November 15, 2012*

**Chemistry**

37.5 x .152 / 25
*November 15, 2012*

**Algebra II**

A runner completes a 16 mile trip, running 8 miles uphill and 8 miles downhill in a total of 4 hours, if his uphill speed is 3 mph slower than his downhill speed, find his downhill speed.
*November 15, 2012*

**Statistics**

One event A is _________________ of another event B if the probabilty of event A has occurred given event B is the same as the probability that A will occur with no knowledge of B. disjoint mutually exclusive dependent independent
*November 15, 2012*

**Statistics**

If you roll a fair die 100 times and 35 of the rolls result in a six, what would be the probability of the outcome of a 2, P(2)? P(2) = 0.02 P(2) = 2 P(2) = 35 P(2) = 0.35
*November 15, 2012*

**math**

Yes Kate is right. ur sexy too jk
*November 14, 2012*

**Science**

Chl has an absorbance peak at 435nm (Soret band) and a peak at 665nm (Qytransition). Calculate the energy gap (in Joules) between the ground and excited states of these two transitions.
*November 14, 2012*

**Physics**

An advertising firm has contacted your engineering firm to create a new advertisement for a local ice-cream stand. The owner of this stand wants to add rotating solid cones (painted to look like ice-cream cones, of course) to catch the eye of travelers. Each cone will rotate ...
*November 13, 2012*

**Finance**

United Technology Corporation (UTC) has $40 million of convertible bonds outstanding (40,000 bonds at $1,000 par value) with a coupon rate of 11 percent. Interest rates are currently 8 percent for bond of equal risk. The bonds have 15 years left to maturity. The bonds may be ...
*November 13, 2012*

**physics**

A 43.3 kg girl is standing on a 125 kg plank. The plank, originally at rest, is free to slide on a frozen lake, which is a flat, frictionless sup- porting surface. The girl begins to walk along the plank at a constant speed of 1.87 m/s to the right relative to the plank. What ...
*November 12, 2012*

**physics**

A 43.3 kg girl is standing on a 125 kg plank. The plank, originally at rest, is free to slide on a frozen lake, which is a flat, frictionless sup- porting surface. The girl begins to walk along the plank at a constant speed of 1.87 m/s to the right relative to the plank. What ...
*November 12, 2012*

**physics**

A(n) 775 N man stands in the middle of a frozen pond of radius 11.2 m. He is un- able to get to the other side because of a lack of friction between his shoes and the ice. To overcome this difficulty, he throws his 1.3 kg physics textbook horizontally toward the north shore, ...
*November 12, 2012*

**Statistics**

Which of the following statements about the correlation coefficient r are true? I. It is not affected by changes in the measurement units of the variables. II. It is not affected by which variable is called x and which is called y. III. It is not affected by extreme values. I ...
*November 12, 2012*

**Statistics**

Suppose a study finds that the correlation coefficient relating family income and SAT scores is r = +0.98. Which of the following are proper conclusions? I. Poverty causes low SAT scores II. Wealth causes high SAT scores III. There is a very strong association between family ...
*November 12, 2012*

**math**

Q) (Speed) Ahmed drives from Abu Dhabi to Dubai. The journey takes him 1 hour 30min and the distance covered is 130km. What is the average speed at which he was travelling (rounded to the nearest 1km/hr)?
*November 12, 2012*

**science**

What is meant by depassivation of reinforcement? State the two main chemical attacks that lead to depassivation
*November 11, 2012*

**Physics**

A file cabinet weighing 1500 N is at rest on the floor. The coefficient of static friction between the floor and the cabinet is 0.5. What is the minimum force required to make the file cabinet move horizontally
*November 10, 2012*

**science**

Abiotic factors
*November 10, 2012*

**math**

how do you go about doing place value puzzles .can you show me an example please(hundredths place,thousandths place,ones place and tenths place
*November 9, 2012*

**Math**

113.50 ? 114.50 ? 115.00
*November 8, 2012*

**physics **

A shopper in a supermarket pushes a loaded 32 kg cart with a horizontal force of 15 N. The acceleration of gravity is 9.81 m/s2 . a) Disregarding friction, how far will the cart move in 3.3 s, starting from rest? Answer in units of m
*November 8, 2012*

**Organic chemistry**

Help me find my percent yield for my witting reaction experiment.... The weight of my final product was: 0.13 I put 0.40 g of benzyltriphenylphosphonium chloride, 0.23 g of 9-anthraldehyde and 1.0ml DMF and 0.5ml of aqueous sodium hydroxide into the flask at the start of the ...
*November 8, 2012*

**Chemistry**

Help me find my percent yield for my witting reaction experiment.... The weight of my final product was: 0.13 I put 0.40 g of benzyltriphenylphosphonium chloride, 0.23 g of 9-anthraldehyde and 1.0ml DMF and 0.5ml of aqueous sodium hydroxide into the flask at the start of the ...
*November 8, 2012*

**Organic Chemistry**

chlorobutane, chloride ion is weaker leaving group
*November 8, 2012*

**Statistics**

Suppose the correlation between two variables is -0.57. If each of the y-values is multiplied by -1, which of the following is true about the new scatterplot? It slopes up to the right, and the correlation is -0.57 It slopes up to the right, and the correlation is +0.57 It ...
*November 8, 2012*

**Statistics**

New York and Pennsylvania have progressive toll roads. Upon entering the toll road the driver receives a ticket marking the location and time of entrance. Upon exiting the mileage is computed and the driver pays the toll. Which of the following would you expect to be true ...
*November 8, 2012*

**science**

Assume an average human cell has a cell cycle of 20 hours. Calculate how many cells there would be after 80 hours.
*November 7, 2012*

**social studies**

what resources did early native american used
*November 7, 2012*

**Physics **

A freight train has a mass of 1.7 × 10^7 kg. If the locomotive can exert a constant pull of 5.2 × 10^5 N, how long would it take to increase the speed of the train from rest to 74.6 km/h? Disregard friction. Answer in units of s
*November 7, 2012*

**fractions from least to greatest**

can you list 3/4, 3/5, and 5/6 from least to greatest
*November 7, 2012*

**History,Art**

Yes I have, I need to provide information about her and her life but I need to know her name.
*November 7, 2012*

**History,Art**

I need to find a picture of 2 paintings: Crimson Rambler by Philip Hale and Automat by Edward Hopper. I also need some assistance with this assignment involving these two paintings. I have to outline a story I would write about the woman in the paintings(I'm supposed to ...
*November 7, 2012*

**Pre Calc**

How to prove tan4x = 1-8 sin squared of cos squared of x
*November 6, 2012*

**chemistry**

Sodium sulfate is slowly added to a solution containing 0.0500 M Ca2 (aq) and 0.0230 M Ag (aq). What will be the concentration of Ca2 (aq) when Ag2SO4(s) begins to precipitate? What percentage of the Ca2 (aq) can be separated from the Ag (aq) by selective precipitation?
*November 5, 2012*

**grammar**

SSS means a compound subject and PPP means a compound predicate if i am right .(1) Blue flages and green rushes grew along the river.I underline blue flags and green rushes once,and grew along bthe river. twice.(2)I underline the flat creek bed once and was made of warm, soft ...
*November 5, 2012*

**grammar**

can you underline the complete subject and the complete predicate of these sentences.show by stating (SSS)and(PPP)also.(1)Blue flags and green rushes grew along the river.(2)The flat creek bed was made of warm ,soft mud. (3)Laura hopped and splashed in the cool creek.(4)The ...
*November 5, 2012*

**Math**

10/12=x/36 360/12=30 yds 1296 inches converted into yards is 36 yds
*November 5, 2012*

**Statistics**

A random sample of 250 men yielded 175 who said they'd ridden a motorcycle at some time in their lives, while a similar sample of 215 women yielded only 43 that had done so. Find a 99% confidence interval for the difference between the proportions of men and women who have...
*November 5, 2012*

**Statistics**

@MathGuru you're useless. You only solve the obvious and then leave us hanging.
*November 5, 2012*

**Statistics**

A random sample of 384 people in Dalto City, a mid-sized city, revealed 112 individuals who work at more than one job. A second random sample of 432 workers from East Dettweiler, another mid-sized city, found 91 people who work at more than one job. To conduct a significance ...
*November 5, 2012*

**biology**

In which sequence did aerobes, anaerobes, chemolithotrophs and cyanobacteria evolve? What evidence is there to support your answer. If someone can answer please. I think its talk about how cyanbactoria evolve.
*November 4, 2012*

**statistics**

A random sample of 250 men yielded 175 who said they'd ridden a motorcycle at some time in their lives, while a similar sample of 215 women yielded only 43 that had done so. Find a 99% confidence interval for the difference between the proportions of men and women who have...
*November 4, 2012*

**statistics**

A random sample of 384 people in Dalto City, a mid-sized city, revealed 112 individuals who work at more than one job. A second random sample of 432 workers from East Dettweiler, another mid-sized city, found 91 people who work at more than one job. To conduct a significance ...
*November 4, 2012*

**Maths**

Let f(x) = tan(x). What is the formula for the conditioning number of f? Evaluate this formula for x =(π/4), 1.01, 1.26, 1.51 (in radians, working to 3 signifi cant figures, the precision that is implicit in this data). Replace each of the expressions for x by its ...
*November 4, 2012*

**Physics**

Hmm this is probably wrong but I was thinking of something like this: M1 = the mass that was in one of the holes R2 = the radius of one of the holes M = mass of the whole original disk R = radius of whole original disk I think the following relation makes sense: M1(R/2)^2 = 0....
*November 2, 2012*

**Physics**

No problem. For my question, I know the goal is to basically subtract the inertia's of the 3 holes from the whole disk's inertia, 0.5*MR^2, but I think what I'm stuck on is how to find that value, or relate it to what we know. The final inertia needs to be 0.81(0.5...
*November 2, 2012*

**Physics**

To reduce its rotational inertia, an engineer proposes drilling three holes in a large wheel of radius R. The holes are to be centered midway between the center and edge of the wheel. What should be their radii (in terms of R) if drilling the holes is to reduce the rotational ...
*November 2, 2012*

**trig**

2 cos(theta-13)= square root of 3
*November 2, 2012*

**maths**

a multiply b =12 b multiply c=13 c multiply d=14 what is the answer for abcd=???
*November 2, 2012*

**Calculus**

Find the volume of the solid obtained by rotating the region enclosed by y=x^3, y=25x, x ≥ 0
*November 1, 2012*

**Calculus**

Find the volume of the solid obtained by rotating the region enclosed by y=x^3, y=25x, x ≥ 0
*November 1, 2012*

**science**

What volume of a 6.0 M NaOH solution would you need to prepare 250.0 milliliters of a 3.0 M NaOH solution?
*November 1, 2012*

**statistic**

in a random sample of 400 voter, 120 plan to vote for candidate A. determine a 95% confidence interval
*November 1, 2012*

**Physics**

Which of the following equations describes the condition for observing the fourth bright fringe in Young's double-slit interference pattern? Assume n = 0 for the central bright fringe. d sinθ = λ d sinθ = 3λ/2 d sinθ = 3λ d sinθ = 4λ
*October 31, 2012*

**Physics**

What is the critical angle of light traveling from benzene (n=1.501) into air? 40.05o 48.22o 41.78o 62.63o
*October 31, 2012*

**Physics, newtons laws**

Let L=length of string=120cm Tsin(a)=mv^2/R, R=Lsin(a), T=mg/cos(a) mgtan(a)=mv^2/Lsin(a), mgsin^2(a)=mv^2cos(a)/L, g(1-cos^2(a))=v^2/L (cos(a)) gLcos^2(a)+v^2cos(a)-gL=0 let x=cos(a), use quadratic formula to solve for x x= (-v^2+sqrt(v^2+4L^2*g^2))/2Lg a=acos(x)=25 degrees
*October 29, 2012*

**geology **

what is the Sample Locality Age (Million years)in Granite: Scottish Highlands, Gabbro: Sudbury Canada and Gneiss: Greenland?
*October 27, 2012*

**physics**

3 meters per second
*October 27, 2012*

**physics**

Suppose you waik 18.0m straight west and then 25.o m straight north. How far are you from your starting point and what is the compass direction of a line connecting your starting point to yourfinal position?
*October 25, 2012*

**science**

10.6
*October 24, 2012*

**science**

How tall is the tree if the sun is at a 53° angle above the horizon and the shadow is 8.0 meters long?
*October 24, 2012*

**Calculus**

A baseball diamond is a 90 foot square with the pitcher's mound at the square's center. A runner races for home at 25 ft/sec. How fast is his distance from the pitcher changing as he crosses the plate?
*October 24, 2012*

**Algebra (Graphing Functions)**

Actually I figured it out.
*October 24, 2012*

**Algebra (Graphing Functions)**

Consider the following function. f(x) = −3x if x < −2 x2 if −2 ≤ x < 2 −3 if x ≥ 2 Please help me find the intervals on which f is increasing, is decreasing, or is constant(in interval notation). As well as the x and y intercepts for ...
*October 24, 2012*

**literature**

Reflecting on this week’s literary readings, as well as your own reading experiences, identify at least one major similarity and one major difference between the forms of the short story and the poem. How do the differences between these literary forms affect how you read...
*October 24, 2012*

**physics**

A ball is attached to one end of a wire, the other end being fastened to the ceiling. The wire is held horizontal, and the ball is released from rest (see the drawing). It swings downward and strikes a block initially at rest on a horizontal frictionless surface. Air ...
*October 23, 2012*

**Boolean algebra **

Simplify this function using Boolean algebra laws? I am stuck on this part of my homework (x2'x1'x0') + (x2'x1x0) + (x2x1x0') I know you have to use distributive laws to do this. Any help is appreciated. Thank you.
*October 23, 2012*

**ict**

I need help woth my cross word
*October 23, 2012*

**Physics**

The wheel is attached to an electric generator and the rotation rate drops from 290 to 230 in 3.5 . What is the average power output?
*October 23, 2012*

**Physics**

Find the energy stored in the solid flywheel of mass 8.0×104 and radius 1.8 when it's rotating at 290
*October 23, 2012*

**Math **

Monday, Mr. C stacked a display case of 80 heads of lettuce. By end of day, some were sold. Tuesday Mr. C counted lettuce left and decided to add an equal number of lettuce (**hint - he doubled the leftovers). At end of Tuesday, he sold the same number as ...
*October 22, 2012*

**chemistry**

oh alright thank you i found out my mistake. thank you sir.
*October 22, 2012*

**chemistry**

Will a fluoride concentration of 1.0 mg/L be soluble in a water containing 200 mg/L of calcium? I got Qsp 1.38 * 10^-8 and Ksp = 3.45*10^-11 does that seem right? and does this mean fluride concentration will be soluble in water containing calcium?
*October 22, 2012*

**chemistry**

thank you sir.
*October 21, 2012*

**chemistry**

Will a fluoride concentration of 1.0 mg/L be soluble in a water containing 200 mg/L of calcium? This is what i found for ksp CaF2<--> Ca(2+) +2F(-) Ksp=(x)(4x^2) where x=solubility Therefore, Ksp=3.7 x 10^-11 and for Qsp I am not sure how to go on about calculating that.
*October 21, 2012*

**Physics**

A 45-kg skater rounds a 5.0-m radius turn at 6.3 m/s. (A.) What are the vertical and horizontal components of the force the ice exerts on her skate blades? (B.) At what angle can she lean without falling over?
*October 21, 2012*

**Cemistry**

This is what i found for ksp CaF2<--> Ca(2+) +2F(-) Ksp=(x)(4x^2) where x=solubility Therefore, Ksp=3.7 x 10^-11 and for Qsp I am not sure how to go on about calculating that.
*October 21, 2012*

**Cemistry**

Will a fluoride concentration of 1.0 mg/L be soluble in a water containing 200 mg/L of calcium?
*October 21, 2012*

**Algebra 2**

x = 0 and x = 3 you did it right.
*October 21, 2012*

**math**

christi rides her bicycle 7 blocks south. 3 blocks east, 5 blocks north, and 8 blocks west. how many blocks has she ridden when she crosses her own path
*October 20, 2012*

**math**

You worked from 2:30pm – 8:45pm with a ½ hour lunch break. Your hourly wage is $7.50/ hour. How much did you earn?
*October 18, 2012*

**chemistry**

a.) The simultaneous oxidation and reduction of a chlorite ion 3ClO-2(aq)-><-2ClO-3(aq) + Cl-(aq. b.) IO-3(aq) + 6OH-(aq) + Cl(aq)-><-IO-5,6(aq) + 3H2O(i).
*October 18, 2012*

**chemistry**

write equilibrium constant expression for each reaction. a) The oxidation of ammonia with CIF3 in a rocket motor NH3(g) + CIF(g)-><-3HF(g) + 1/2N2 + 1/2Cl(g) b.) The simultaneous oxidation and reduction of a chlorite ion. 3Cl-2(aq)-><-2ClO-3(aq) + Cl-(aq) c.) IO-3(...
*October 18, 2012*

**Math**

Suppose you draw 5 cards out of a deck of 52 and get 2 spades and 3 hearts. What is the probability that the first card drawn was a spade?
*October 17, 2012*

**physics**

a baseball is thrown horizontally at a velocity of 35 m/s from a height of 1.5 m. How long does it take to hit the ground? how far does it travel?
*October 17, 2012*

**Math**

simple. Set up two fractions like so: 159mi/5.3gal =x/1gal answer would be 30 miles.
*October 17, 2012*

**chemistry .chemistry**

obtanin a piece of comcentrated acetic acid and 10 ml of di- water . bring the content of this beaker to a gentle boil using a low flame on the Bunsen burner . boild for about 3minutes , alow to cool and then remove the steel wool ball . what is formula? Ans : Fe + 2CH3COOH...
*October 17, 2012*

**chemistry**

obtanin a piece of comcentrated acetic acid and 10 ml of di- water . bring the content of this beaker to a gentle boil using a low flame on the Bunsen burner . boild for about 3minutes , alow to cool and then remove the steel wool ball . what's happened in procedure? i ...
*October 16, 2012*

**chemistry**

thank you
*October 16, 2012*

**chemistry**

From which sublevel are the first 2 electrons for Fe removed from ______ From which sublevel is the next electron for Fe removed from _________ Why does the removal of electrons stop at this subleval and number of electron?? Please help me !!!
*October 16, 2012*

**chemistry --**

What determines whether 2 or 3 electrons will be removed from Fe when it reacts with another chemical or element?
*October 16, 2012*

**math**

The value of a new car decreases exponentially.Suppose your mother buys a new car for 22,000. The value of the car decreases by 20% each year. a.what is the initial price of the car. The decay factor. b. write an equation to model the value of the cars years after she buys it...
*October 14, 2012*

**chemistry**

compare the emission color of lithium to that of potassium .what can you conclude about these two elements and the energy levels that their electron transition?
*October 12, 2012*