Tuesday

February 21, 2017
Total # Posts: 1,166

**statistics**

A researcher wishes to estimate the mean height of women aged between 60 and 65 in the US. She desires a margin of error of 0.2 inches. Past studies suggest that a population standard deviation deviation of 3.2 inches is reasonable. Estimate the minimum sample size needed to ...

*January 23, 2012*

**physics**

CHICKEN NUGGETS = GOLDEN TAR

*January 14, 2012*

**physics**

What is the pressure at the bottom of a river (12 m deep) if the air pressure over the river is 98.23 kPa? The density of the river water is 988 kg/m3.

*December 15, 2011*

**physics**

What is the pressure at the bottom of a river (12 m deep) if the air pressure over the river is 98.23 kPa? The density of the river water is 988 kg/m3.

*December 15, 2011*

**Spanishanother question**

5. También yo recibí/he recibido muchos regalos de mi familia.

*December 15, 2011*

**Physics**

v = u + a*t so t = (v-u)/a x = t (v+u)/2 substituting for t, x = (v+u)(v-u)/2a put in known values: 13 = (5)(-5)/2a a = -25/26 m/s^2 f = m*a u(k) * f(normal) = m*a u(k) *m*g = m*a u(k) = a/g u(k) = -25/26 /9.81 = 0.098 where u(k) = coefficient of friction for magnitude of ...

*December 11, 2011*

**physics**

One dimension. In Fig. 13-32, two point particles are fixed on an x axis separated by distance d. Particle A has mass mA and particle B has mass 4.00 mA. A third particle C, of mass 80.0 mA, is to be placed on the x axis and near particles A and B. In terms of distance d, at ...

*December 6, 2011*

**physics**

One dimension. In Fig. 13-32, two point particles are fixed on an x axis separated by distance d. Particle A has mass mA and particle B has mass 4.00 mA. A third particle C, of mass 80.0 mA, is to be placed on the x axis and near particles A and B. In terms of distance d, at ...

*December 6, 2011*

**Physics**

You have a 2.4 m high platform that is level on top. A spring launcher is located on the top so that it launches objects horizontally. You want to launch a 0.70 kg ball so that it hits at target on the ground 6.0 m away from the base. If the spring constant is 500 N/m, what ...

*November 17, 2011*

**algebra**

if the lengths of a triangle are y, y-1 and 7 what is the length of the longest side if the perimeter is 65

*November 15, 2011*

**Physics**

What is the angular momentum (in kg*m*m/s) of a 790 gram symmetrical rotating bar which is 2.85 m long and spinning at 245 rpm about the center of the bar?

*November 14, 2011*

**organic chemistry**

Could you use NaOH to separate acetylsalicylic acid (aspirin) and acetaminophen (Tylenol) by acid-base extraction?

*November 13, 2011*

**spanish**

I have to translate this to indirect style is this correct? Original:Pero cien años después, las personas negras todavía no son libres. Cien años después, la vida de las personas negras sigue todavía tristemente atenazada por los ...

*November 7, 2011*

**Physics**

A 72.0 kg skateboarder wants to just make it to the upper edge of a "quarter pipe", a track that is one-quarter of a circle with a radius of 4.65 m. What speed (in m/s) does he need at the bottom assuming that the local acceleration due to gravity is 9.80 m/s2?

*November 2, 2011*

**n/a**

Is it not possible to talk to tutors or students directly?

*October 31, 2011*

**Math**

company is considering offering child care for their employees. They wish to estimate the mean weekly child-care cost of their employees. A sample of 10 employees reveals the following amounts spent last week in dollars.

*October 30, 2011*

**Physics**

A 72.0 kg skateboarder wants to just make it to the upper edge of a "quarter pipe", a track that is one-quarter of a circle with a radius of 4.65 m. What speed (in m/s) does he need at the bottom assuming that the local acceleration due to gravity is 9.80 m/s2?

*October 27, 2011*

**Physics, help with a similar problem I just posted**

I posted a the same problem with different numbers a minute ago. The answer to the problem below (same as the other with different numbers) is 28 degrees. Maybe this will help to solve it? Thanks! A block is hung by a string from the inside roof of a van. When the van goes ...

*October 19, 2011*

**physics**

A block is hung by a string from the inside roof of a van. When the van goes straight ahead at a speed of 28.9 m/s, the block hangs vertically down. But when the van maintains this same speed around an unbanked curve (radius = 144 m), the block swings toward the outside of the...

*October 19, 2011*

**Physics**

A 9.60 g coin is placed 10.7 cm from the center of a turntable. The coin has a coefficient of static friction of 0.80 and a coefficient of kinetic friction of 0.60 with the turntable. The turntable's angular velocity slowly speeds up until the coin starts to slide off. ...

*October 17, 2011*

**german**

[german] Sie sind sehr hübsch. = [en] You (formal) are very beautiful.

*October 17, 2011*

**physics**

a runner run halfway around a circular track whose radius is 60 meters in 45 secs what is the average velocity? what is the average speed?

*October 16, 2011*

**Physics**

light travels at a constant speed of 3x10*11 cm/sec. how long does it take light to reach the earth a distance of 1.5x10*8 km. give the answers in seconds and minutes.

*October 16, 2011*

**Chemistry**

when testing for antimony, what reagent prevents tin from reacting with the H2S to form SnS2? What reagent is used to identify copper and explain its function.

*October 16, 2011*

**Chemistry**

thanks i wish they were in my book

*October 16, 2011*

**informal Logic**

correct, but something that can always be revised? But can't find the exact answer in text, urrrg!

*October 16, 2011*

**physics**

A thin 2kg box rests on a 6kg board 50cm long with 20cm hanging off the edge of a table. How far can the center of the box be from the end of the table before the board begins to tilt?

*October 12, 2011*

**Physics**

Compressed air is used to fire a 41.0 g ball vertically upward from a 1.0-m-tall tube. The air exerts an upward force of 3.7 N on the ball as long as it is in the tube. How high (in m) does the ball go above the top of the tube, assuming that the acceleration due to gravity is...

*October 10, 2011*

**Algebra Question 1**

business A=x business B=2x-20 business C=2x-20+2(2x-20)-200 x+2x-20+2(2x-20)-200=1035 x+2x-20+4x-40-200=1035 7x=1035+20+40+200 7x=1295 x=185 Bus. A pledged $185 million Bus. B pledged 185x2=370-20=350 million Bus. C pledged 350x2=700-200=500million 185+350+500= $1035 million

*October 6, 2011*

**math**

You round down and say 500*3 which is 1500 then go 600*3 which is 1800. The number is between 1500 and 1800.

*October 5, 2011*

**Physics**

No idea

*October 2, 2011*

**Physics**

A car is traveling at 95km/hr when it collides with a stone wall. The car comes to rest after the first 30 cm of the car is crushed.what was the average horizontal force acting on a 68.1 kg driver while the car came to rest? If 5 cardboard boxes each 1.25 m wide and filled ...

*October 2, 2011*

**german**

1. Paragraph about some event in the past and how I reflect on it - What do you want to write about? - What don't you know? 2. Wetter - vocabulary? 3. Jahreszeiten - Frühling, Sommer, Herbst und Winter? 4. Partizip - mit|machen - auf|passen - an|kommen - ein|fliegen...

*October 2, 2011*

**trig**

The captain of a ship at sea sights a lighthouse which is 120 feet tall. The captain measures the the angle of elevation to the top of the lighthouse to be 19 ^\circ. How far is the ship from the base of the lighthouse?

*October 1, 2011*

**physics**

In the figure below, m1 = 10.0 kg and m2 = 4.5 kg. The coefficient of static friction between m1 and the horizontal surface is 0.60, and the coefficient of kinetic friction is 0.30. m1 is on a table connected to m2 by a string that is on a pulley. m2 is hanging off the table ...

*September 28, 2011*

**algebra**

a purse contains 26 coins, some of which are dimes and the rest are nickels. Altogether, the coins are worth more than $2.10. At least how many dimes are in the purse?

*September 25, 2011*

**physics**

A truck at rest at a stoplight accelerates uniformly with acceleration a = 9 meters/second2 for 6.8 seconds after the light turns green. What is the speed of the truck in meters/second after that time interval?

*September 20, 2011*

**geometry**

if B is the midpoint of AC=1/2AC

*September 20, 2011*

**geometry**

g is between f and h. fh=8x,fg=6x+7, and gh+28. find fh

*September 15, 2011*

**algebra**

simplify 8-(y-1)-(10-4y)

*September 14, 2011*

**physics**

A = 51.15 V= 638.8

*September 14, 2011*

**physics**

correct me if im wrong solve for a = 102 and v = 1249

*September 14, 2011*

**physics**

ok i get

*September 14, 2011*

**physics**

where did you get the 144

*September 14, 2011*

**physics**

a uniformly accelerating train passes a green light signal at25.0 km/hr it passes a second light 125m farther down the track 12.0s later what is the trains acceleration? what is the trains velocity at the second light?

*September 14, 2011*

**physics**

a uniformly accelerating train passes a green light signal atk mhr it passes a second light 125m farther down the track 0s later what is the trains acceleration? what is the trains velocity at the second light?

*September 14, 2011*

**English Correction**

2-orient 4- 5-discern

*September 14, 2011*

**math**

moving straight ahead pg 12 #3

*September 11, 2011*

**math**

moving straight ahead pg 12 #3

*September 11, 2011*

**Calculus**

Sketch the region enclosed by the given curves. Decide whether to integrate with respect to x or y. Then find the area of the region. 2y=3sqrtx , y=3 , 2y+2x=5

*August 17, 2011*

**public health**

Where did the practice of public health first originate? North america South America Asia is it North America?

*August 8, 2011*

**English 12**

Does anyone know what book will we be using for poems,short stories and literature in Grade 12?

*July 23, 2011*

**chemistry**

I understand how to do the steps. but the wording is different on this problem, that is what I don't understand?

*July 13, 2011*

**chemistry**

What is the percent yield for the reaction PCl3(g) + Cl2(g) --> PCl5(g) if 119.3 g of PCl5 are formed when 61.3 g of Cl2 react with excess PCl3? I don't understand how to set this up?

*July 13, 2011*

**chemistry**

iron(III) oxide reacts with carbon monoxide gas to form solid iron metal and carbon dioxide gas: Fe2O3 + 3 CO --> 2 Fe + 3 CO2 If you begin the reaction with 84.34 g of iron(III) oxide and 68.87 g of CO, which reactant will be in excess at the end of the reaction and how ...

*July 12, 2011*

**Public health**

monitoring of reports of communicable diseases in the community types: descriptive and analytic epidemiology is used to determine such

*June 28, 2011*

**chemistry**

How many grams of O2 are required to burn 46.0 grams of C5H12?

*June 22, 2011*

**history**

Describe how influential the Cold War has been on the world of today.

*June 11, 2011*

**math**

Block method: 8 teachers for 5 courses [#]*[#]*[#].... [8]*[7]*[6]*[5]*[4]= ?

*June 7, 2011*

**Statistics**

A bag of marbles has 5 Green, 4 Red, and 3 yellow marbles. Three marbles are randomly drawn from the bag, without replacement: What is the probability that at least one of the three marbles drawn are red? What is the probability that only one of the three marbles drawn is red...

*June 7, 2011*

**MATH please help**

thanks

*June 6, 2011*

**MATH please help**

Out of 42 kids in a class twice as many failed Ela as math,4 failed both. If 7 failed neither, find how many failed each subject. Please help and show work it would be great thanks i really need help thanks

*June 6, 2011*

**Statistics**

Under what circumstances does the sampling distribution of the proportion approximately follow the normal distribution?

*June 3, 2011*

**Geometry**

V of cube = side*side*side = 6*6*6 = 216 V of hemisphere = 1/2 of V of sphere = 4/3*pi*radius cubed = 1/2(4/3(pi 3cubed))= 1/2(4/3(pi 27)= 1/2(36pi)= [18pi meters] or [56.52 meters]

*June 1, 2011*

**Science**

Using the balanced equation for this reaction, calculate the volume of CO2 that should be produced by the decomposition of 2.21g of CuCO3•Cu(OH)2 at STP.

*June 1, 2011*

**math**

20+d+10 where d=30, 20+30+10=60minutes or 1 hour

*June 1, 2011*

**Physical Science 2nd Semester**

I hope this answers your question!!

*May 24, 2011*

**world issuse**

I'm a 7 letter word u read daily,my 5th 6th and 7th letter increase each year,my 3rd n 4th letter are the same,my 3rd 2nd n 5th letter cover 75% of the world.

*May 24, 2011*

**english**

Thanx

*May 23, 2011*

**english**

Pls Re-arrange this word aidgact

*May 23, 2011*

**english**

Is incense a social problem and why ?

*May 14, 2011*

**Algebra**

what does the sigma notation look like for the sequence 1/4,-1/9,1/16,-1/25

*May 12, 2011*

**math**

If a a sheet of cardboard measures 9 feet by 6 feet and is made into a perfect cube, what would the length of each edge be?

*May 9, 2011*

**math**

If a a sheet of cardboard measures 9 feet by 6 feet and is made into a perfect cube, what would the length of each edge be?

*May 9, 2011*

**Chemistry**

Calculate the pH of a solution that is made by mixing 10.00 mL of 0.2500 M HCl with 35.00 mL of .1500 M HNO3 and diluting the mixture to a total volume of 100.00 mL

*May 5, 2011*

**Science**

I would recommend to check out a website called physmatixsolve They helped me with a tough question i got in my Physics homework, classical mechanics. The amazing thing is that they really sent me the solution in less than 24 hours, which is pretty neat.

*April 25, 2011*

**Physics**

A 395cm oscillator has a speed of 104.5cm/s when its displacement is 2.80cm and 74.5cm/s when its displacement is 6.60cm. What is the oscillator's maximum speed?

*April 24, 2011*

**Physics**

A 20 cm long, 180g rod is pivoted at one end. A 17g ball of clay is stuck on the other end. What is the period if the rod and clay swing as a pendulum?

*April 24, 2011*

**spelling**

future

*April 20, 2011*

**Math**

Kelly takes 6 laps and Angela takes 5 laps so they both meet at the starting point at 90 minuets...1 hour and 30 minuets.

*April 20, 2011*

**Math**

If angle x lies in quadrant 3 and cos(x)= -0.6 Find cos(3pi/2-x)

*April 20, 2011*

**trig**

angle x lies in quadrant 3 and cos(x)=-.6. Find cos(3pi/2-x)

*April 19, 2011*

**A level english literature**

I need to write an essay comparing estrangement and alienation in cat on a hot tin roof and awakening, I sort of know what to write but I'm struggling to get a good opening to my essay. Help!

*April 19, 2011*

**Physics**

Fresh snow is about one-tenth as dense as liquid water. How much latent heat is released in storm clouds per square kilometer of surface area by the freezing of water droplets if the storm deposits a 30-cm-deep layer of fresh snow? Q = LfM where the mass is the density of ...

*April 14, 2011*

**Physics**

PROJECTILE LAUNCHED FROM EARTH'S SURFACE? A projectile is shot straight up from the earth's surface at a speed of 1.20×10^4km/hr. How high does it go? (answer in km) Supposed to solve this using F=G(mm/2r)...?

*April 12, 2011*

**Physics**

Speed of Asteroids With the same Radius? Two spherical asteroids have the same radius R . Asteroid 1 has mass M and asteroid 2 has mass 2M. The two asteroids are released from rest with distance 10R between their centers. What is the speed of each asteroid just before they ...

*April 12, 2011*

**Physics**

Finding a Lunar lander's Thrust? A 6000kg lunar lander is in orbit 50km above the surface of the moon. It needs to move out to a 200km -high orbit in order to link up with the mother ship that will take the astronauts home. How much work must the thrusters do in joules?

*April 12, 2011*

**Physics**

An 9.00-cm-diameter, 400 sphere is released from rest at the top of a 1.90-m-long, 20.0 incline. It rolls, without slipping, to the bottom. A) What is the sphere's angular velocity at the bottom of the incline? B) WWhat fraction of its kinetic energy is rotational?

*April 10, 2011*

**physics please help!**

Suppose that 90 g of hot water at a temperature of 75 degrees C is poured into a cavity in a very large block of ice at 0 degrees C. (a) What will be the final temperature of the water in the cavity? (b) What mass of ice must melt in order for the water to cool down to the ...

*April 8, 2011*

**math**

the density of a diamond is 3.52 grams per cubic centimeter. Sally has a diamond that has a volume of 20 mm^3. What is the weight of the diamond?.

*April 6, 2011*

**math**

Thank you!!

*April 6, 2011*

**math**

The density of a crystal is 2.65 grams per cubic centimeter. Ryan has a rectangular prism made of quartz. It measures 10 cm by 10 cm by 6 cm. Find the weight of this crystal in kilograms.

*April 6, 2011*

**math**

i am greater than 15 and less than 40.if you double me, i become a number that ends in 0.1/5 of me is equal to 5.

*April 5, 2011*

**Chemistry**

Thanks a lot man!

*April 3, 2011*

**Chemistry**

The Ksp for a certain metal hydroxide, M(OH)2 (molar mass = 127) is 3.5 × 10-19. What is the pH for a saturated solution of this hydroxide? Confused on how to set up this problem...

*April 3, 2011*

**Maths**

What is 5y=9+2y

*March 30, 2011*

**Physics**

An object initially at a temperature of 80 C cools by 1 C in a time of 15 s when placed in a 20 C room When the object's temperature reaches 50 C, what is the average rate at which the object cools?

*March 28, 2011*