Sunday

February 14, 2016
Total # Posts: 7,298

**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**

On earth, two parts of a space probe weigh 18000 N and 3100 N. These parts are separated by a center-to-center distance of 15 m and may be treated as uniform spherical objects. Find the magnitude of the gravitational force that each part exerts on the other out in space, far ...
*October 23, 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*

**soicial studys help plz**

Let me check this listen body if you want the answer to the last question research or just dread this 1. C 2. Dr 3. B
*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*

**soical studys**

Actually Samantha is right Kia is not 2 is b
*October 20, 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*

**7th grade social studies Ms.Sue please**

Savanna is right
*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*

**7th grade social studies help quick please**

Listen to these answers ^ l
*October 10, 2012*

**chemistry**

How do you convert that to kJ/mol
*October 10, 2012*

**Repost-Physics 1**

A crate of mass 48 kg is pushed up a frictionless ramp by a person as shown in the figure below. Calculate the work done by the person in pushing the crate a distance of 11 m as measured along the ramp. Assume the crate moves at constant velocity. _____J
*October 9, 2012*

**Repost-Physics 1**

Two railroad cars, each of mass 2.2 104 kg, are connected by a cable to each other, and the car in front is connected by a cable to the engine as shown in the figure below. The cars start from rest and accelerate to a speed of 1.7 m/s after 1 min. a)Find the work done by cable...
*October 9, 2012*

**Repost-Physics 1**

A car is pushed along a long road that is straight, horizontal, and parallel to the x direction. a)The horizontal force on the car varies with x as shown in the figure. What is the work done on the car by this force? (Let a = 100 N.) _____J b)What is the work done by gravity ...
*October 9, 2012*

**Repost-Physics 1**

A horizontal force of 30 N pulls a block of mass 2.5 kg across a level floor. The coefficient of kinetic friction between the block and the floor is ìK = 0.25. If the block begins with a speed of 2.0 m/s and is pulled for a distance of 18 m, what is the final speed of ...
*October 9, 2012*

**Repost-Physics 1**

A skier of mass 109 kg travels down a frictionless ski trail. a)If the top of the trail is a height 218 m above the bottom, what is the work done by gravity on the skier? _____J b)Find the velocity of the skier when he reaches the bottom of the ski trail. Assume he starts from...
*October 9, 2012*

**Repost-Physics 1**

Consider a roller coaster that moves along the track shown in the figure below. Assume all friction is negligible and ignore the kinetic energy of the roller coaster's wheels. Assume the roller coaster starts with a speed of 19 m/s at point A. Find the speed of the roller ...
*October 9, 2012*

**physics**

A 110 kg object moves in a horizontal straight line with an initial speed of 54 m/s. If it is stopped along that line with a deceleration of 1.90 m/s2 what magnitude of force is required?
*October 9, 2012*

**physics**

A 110 kg object moves in a horizontal straight line with an initial speed of 54 m/s. If it is stopped along that line with a deceleration of 1.90 m/s2 what magnitude of force is required?
*October 9, 2012*

**Physics**

assuming there is no air friction, A) yes B) (10+1.35)-8.65= 2.7m
*October 9, 2012*

**Math**

10/2 X - 3/2 X= 7/2 X= 3.5X
*October 9, 2012*

**4th grade math**

no problem
*October 9, 2012*

**4th grade math**

72
*October 9, 2012*

**Physics 1**

Consider a roller coaster that moves along the track shown in the figure below. Assume all friction is negligible and ignore the kinetic energy of the roller coaster's wheels. Assume the roller coaster starts with a speed of 19 m/s at point A. Find the speed of the roller ...
*October 8, 2012*

**Physics 1**

A skier of mass 109 kg travels down a frictionless ski trail. a)If the top of the trail is a height 218 m above the bottom, what is the work done by gravity on the skier? _____J b)Find the velocity of the skier when he reaches the bottom of the ski trail. Assume he starts from...
*October 8, 2012*

**Physics 1**

A horizontal force of 30 N pulls a block of mass 2.5 kg across a level floor. The coefficient of kinetic friction between the block and the floor is μK = 0.25. If the block begins with a speed of 2.0 m/s and is pulled for a distance of 18 m, what is the final speed of the...
*October 8, 2012*

**Physics 1**

A car is pushed along a long road that is straight, horizontal, and parallel to the x direction. a)The horizontal force on the car varies with x as shown in the figure. What is the work done on the car by this force? (Let a = 100 N.) _____J b)What is the work done by gravity ...
*October 8, 2012*

**Physics 1**

Two railroad cars, each of mass 2.2 104 kg, are connected by a cable to each other, and the car in front is connected by a cable to the engine as shown in the figure below. The cars start from rest and accelerate to a speed of 1.7 m/s after 1 min. a)Find the work done by cable...
*October 8, 2012*

**Physics 1**

A crate of mass 48 kg is pushed up a frictionless ramp by a person as shown in the figure below. Calculate the work done by the person in pushing the crate a distance of 11 m as measured along the ramp. Assume the crate moves at constant velocity. _____J
*October 8, 2012*

**Physics 1**

A crate of mass 42 kg is pushed across a level floor by a person. If the person exerts a force of 20 N in the horizontal direction and moves the crate a distance of 11 m, what is the work done by the person? _____J
*October 8, 2012*

**english**

I'm trying to help someone with homework. And I need too know a paragraph including does words, so i can understand it and help them.
*October 8, 2012*

**english**

Can you give me a short story in narrative form using these words:renounced, swaggering, raucous, insolently, simultaneously, incredulously, cynically, maneuvered, deprived, haggard, institution, reformation.
*October 8, 2012*

**Math**

Insert a set of parentheses in this expression so that ii is equivalent to 3y+10: 4y-3x-y+2x-8+5x+2
*October 7, 2012*

**algebra 2**

i'm trying to solve this system of equations with 3 variables 5a-b+3c=5 2a+7b-2c=5 4a-5b-7c=-65 i tried to make the first equation like a=something so i could substitute it in to the 2nd equation, however i get decimals so it doesnt work how do i do this problem?
*October 7, 2012*

**Chemistry**

What is the moles of NaOH when molarity is .2744 125 mL flask Mass 9.398 Volume 29.90
*October 6, 2012*

**Alg 2**

Today we learned how to solve systems of equations with 3 variables, however my teacher didn't go over how to do a problem where not every single equation in the system has the 3 variables. Can someone point me to a place that explains this? the kind of problem im talking ...
*October 5, 2012*

**math**

351
*October 5, 2012*

**algebra**

Simplify the expression. 22+ (32 – 42)
*October 4, 2012*

**precalculus**

81.125
*October 4, 2012*

**Physics 1**

T^2/R^3=4pi^2/GM ---->T^2/5.8e11=4pi^2/(6.673e-11)(1.99e30) is this how it's supposed to be setup?
*October 4, 2012*

**Physics 1 **

The region of the solar system between Mars and Jupiter contains many asteroids that orbit the Sun. Consider an asteroid in a circular orbit of radius 5.8 1011 m. Find the period of the orbit. _____s
*October 4, 2012*

**Physics 1**

I'm sorry but I don't understand what these masses should be..I keep finding different ones...
*October 4, 2012*

**Physics 1**

Find the ratio of your weight on the Earth to your weight on the surface of the Earth's Moon. WEarth/WEarth's Moon=
*October 4, 2012*