Saturday

February 6, 2016
Total # Posts: 373

**chemistry**

If 21.0 L of gas is held at a pressure of 7.80 atm and a temperature of 900.0 K, what will be the volume of the gas if the pressure is decreased to 4.50 atm and temperature decreased to 750.0 K?
*July 3, 2013*

**statistics & probability**

according to a survey, 30% of 18-25 year olds have blue eyes. In a random sample of 8 people in this age group what is the probability that exactly 0 have blue eyes?
*June 27, 2013*

**writing**

Using elipsess and brackets Add punctuation to the following excerpt. Writing under the name of Diedrich Knickerbocker Washington Irving aimed his potent satire at as diverse topics as political rivals such as Thomas Jefferson to the very ideal of looking back on the past ...
*June 14, 2013*

**geometry**

Which of the following statements is true?Select one of the options below as your answer:A. A 25o angle is congruent to a 25o angle. B. Two intersecting lines form two pairs of congruent angles. C. It is possible for congruent angles to add up to 90o. D. All of the above are ...
*June 12, 2013*

**Math**

A math class has girls and boys in the seventh grade and girls and boys in the eighth grade. The teacher randomly selects a seventh grader and an eighth grader from the class for a competition. What is the probability that the students she selects are both girls? Write your ...
*May 1, 2013*

**Physics-- please help me finish!!**

Ive tried using the formulas my teacher gave me, however I can't seem to get the right answers. Please help! A 1.4-kg block hangs from a spring. A 363-g body hung below the block stretches the spring 2.6 cm farther. What is the spring constant? When the 363-g body is ...
*April 26, 2013*

**chemistry**

The question I am having trouble with is: Scientists originally were uncertain whether the oxygen gas produced during photosynthesis came from CO2, H2O, or from both. How could radioisotope tracers be used to settle that question? Chemistry - DrBob222 6CO2 + 6H2O ==> ...
*April 15, 2013*

**Chemistry**

The question I am having trouble with is: Scientists originally were uncertain whether the oxygen gas produced during photosynthesis came from CO2, H2O, or from both. How could radioisotope tracers be used to settle that question?
*April 14, 2013*

**Chemistry**

Calculate the mass of 0.0122 moles of: a) Si3N4 b) (CH3)3 N
*April 2, 2013*

**Pre-Algebra **

What association would you expect if graphing height and weight?
*March 19, 2013*

**math**

6,000pounds
*March 17, 2013*

**honors algebra**

the area of a triangle is 105 square feet. the height is two more than four times the base. find the base and height of the triangle
*March 6, 2013*

**Physics**

An air-track cart of mass 0.10 is moving with a speed 1.2 to the right when it collides with a cart of mass 0.24 that is at rest. Each cart has a wad of putty on its bumper, and hence they stick together as a result of their collision. Suppose the average contact force between...
*March 2, 2013*

**chemistry**

Suppose of copper (II) nitrate is dissolved in of a aqueous solution of sodium chromate. Calculate the final molarity of nitrate anion in the solution. You can assume the volume of the solution doesn't change when the copper (II) nitrate is dissolved in it. Round your ...
*February 19, 2013*

**Physics**

A person stands 2.0 m away from the reflecting surface of a plane mirror. What are the image characteristics?
*February 13, 2013*

**Physics**

A small dog sits 1.5 m in front of a plane mirror. Where is the dog's image in relation to the mirror?
*February 13, 2013*

**Physics**

A woman 2.00 m tall stands 3.5 m in front of a plane mirror. (a) What is the minimum height the mirror must be to allow the woman to view her complete image from head to foot? Assume that her eyes are 10 cm below the top of her head.(b) What would be the required minimum ...
*February 13, 2013*

**Physics**

A woman fixing her hair holds a plane mirror 30 cm away from the front of her face so as to look into a plane mirror on the bathroom wall behind her. She is 90 cm from the wall mirror. Approximately how far does the image of the back of her head appear in front of her?
*February 13, 2013*

**Math**

What is the rule for 2 to 3 and 9 24.
*February 12, 2013*

**dakota valley**

what is areoglhmet
*February 12, 2013*

**physics**

(part 1) An athlete whirls an 8.1 kg hammer tied to the end of a 1.4 m chain in a horizontal circle. The hammer moves at the rate of 0.597 rev/s. What is the centripetal acceleration of the hammer? Assume his arm length is included in the length given for the chain. Answer in ...
*February 12, 2013*

**Physics**

An Olympic skier moving at 19 m/s down a 26 degree slope encounters a region of wet snow and slides 136 m before coming to a halt. What is the coefficient of friction between the skis and the snow? ( g = 9.81 m/s2)
*January 27, 2013*

**Math**

4y is 55 percent of what number
*January 7, 2013*

**Math**

I have a garden that is 50 ft x 18 ft and my friend has a garden that is 30 ft X 15 ft. Why is the area of my garden twice the size of my friend's garden?
*December 11, 2012*

**Physics**

35 m/s or 130 km/hr
*November 25, 2012*

**Science**

as you push a lawn mower , the horizontal force is 300n, if you push the mower a distance of 500m, how much work do you do?
*November 18, 2012*

**physics pre-ap**

A(n) 1100 kg car is parked on a 4 incline. The acceleration of gravity is 9.8 m/s2 . Find the force of friction keeping the car from sliding down the incline. Answer in units of N
*November 15, 2012*

**Physics **

The Trans-Alaskan pipeline is 1300 km long, reaching from Prudhoe Bay to the port of Valdez, and is subject to temperatures ranging from -72°C to +38°C. (a) How much does the steel pipeline expand due to the difference in temperature? (The coefficient of linear ...
*November 14, 2012*

**Intro to Physics **

The Trans-Alaskan pipeline is 1300 km long, reaching from Prudhoe Bay to the port of Valdez, and is subject to temperatures ranging from -72°C to +38°C. (a) How much does the steel pipeline expand due to the difference in temperature? (The coefficient of linear ...
*November 14, 2012*

**Intro to Physics**

(a) An ideal gas occupies a volume of 3.0 cm3 at 20°C and atmospheric pressure. Determine the number of molecules of gas in the container. _____________molecules (b) If the pressure of the 3.0-cm3 volume is reduced to 2.4 × 10−11 Pa (an extremely good vacuum) ...
*November 14, 2012*

**Intro to Physics**

An air bubble has a volume of 1.65 cm3 when it is released by a submarine 105 m below the surface of a lake. What is the volume of the bubble when it reaches the surface? Assume the temperature and the number of air molecules in the bubble remain constant during its ascent. ...
*November 14, 2012*

**Intro to Physics **

At what temperature would the rms speed of a nitrogen atom equal the following speeds? (Note: The mass of a nitrogen atom is 2.324 10-26 kg.) (a) the escape speed from Earth, 1.12 104 m/s ___________K (b) the escape speed from the Moon, 2.37 103 m/s ___________K
*November 14, 2012*

**science**

About 70% of the human population can taste the bitter chemical phenylthiocarbamide (PTC), which is found in foods like broccoli. The allele, T, for tasting PTC is dominant over the allele, t, for not tasting it. Calculate the allele frequencies using the Hardy-Weinberg ...
*November 10, 2012*

**chemistry**

How many moles are in 4.80 grams on SnO2?
*November 1, 2012*

**math**

John has traveled from a distant planet to spend one earth year visiting with us. However, one year on earth is not the same as one year on john's planet. on john's planet: 10 seconds = 1 minute 10 minutes = 1 hour 10 hours = 1 day 10 days = 1 week 10 weeks = 1 month ...
*October 18, 2012*

**Health**

Empty calories are defined as ________. A. Calories from dairy products only B. Calories from low-fat foods and/or fruits and vegetables C. Calories from water and other foods or beverages that have zero calories D. Calories from solid fats and/or added sugars
*October 16, 2012*

**physics**

determine the tension in each cable below. draw a force diagram for the system before solving the problem. Case A- ball suspended on one cable Case B- ball suspended on by two cables
*October 11, 2012*

**trig**

Find the following values for each function a. f(0) b. f(-1) c. f(-x) d. f(x+1) f(x)=2x^2+3x-4 I you plug in the value for each x, I just want to check my answers. Thanks.
*October 9, 2012*

**Math**

Find (fog)(2) and (gof)(-2) f(x)=Square root of 4-x; g(x)=1-3x^2 Show work.
*October 9, 2012*

**health**

The key to using a pedometer to meet the Physical Activity Guidelines for Americans is to _________. A. First set a time goal and then calculate how many steps are needed each day to reach that goal B. First set a time goal and then calculate how rigorous the steps need to be ...
*October 5, 2012*

**math**

10 x 10
*October 4, 2012*

**managerial economics**

You sell 1/3 of the world an iphone at $400. 1/3 a year later for $300.00 and after 1/3 of the world at $250. Those people would not buy unless price is dropped so you get your initial huge profit on the coustomers that can not wait then continue to drop price until all ...
*September 30, 2012*

**math**

If you have 30 white lego bricks, 42 red lego bricks, and 45 black lego bricks and you pull them out of a bag one at a time until one is left, what is the probability the last brick will be black
*September 19, 2012*

**Math ASAP**

I think 6 an 8 are right
*September 19, 2012*

**Math ASAP **

1.-80%(-2) (=,<,>) 120/3 2.-1750%70 (=,<,>) -1008/48 3.240/-80 (=,<,>) -150/50 4.675/-45 (=,<,>) 865/-51 5.-3755%x= -15 6.22=x%(-34) X=-748 7.x%(-17)=-35 8.-680 % x =53 X=-13
*September 19, 2012*

**Math**

ASAP NEED HELP FAST PLZZ
*September 19, 2012*

**Math**

1.-80%(-2) (=,<,>) 120/3 2.-1750%70 (=,<,>) -1008/48 3.240/-80 (=,<,>) -150/50 4.675/-45 (=,<,>) 865/-51 5.-3755%x= -15 6.22=x%(-34) X=-748 7.x%(-17)=-35 8.-680 % x =53 X=-13
*September 19, 2012*

**math**

-84-(-55)=-139
*September 11, 2012*

**5th grade religion**

no it doesnt
*September 5, 2012*

**5th grade religion **

For whom do members of the JVC works? plz don't give me an answer to look at on wikapieda that website does not tell the truth thanks
*September 5, 2012*

**5th grade religion**

For whom do members of the JVC work?
*September 5, 2012*

**math**

they have to take the 25 out there there is no 25 in the first number
*September 5, 2012*

**math**

they put in the 25 and there is know 25 in the first number
*September 5, 2012*

**5th grade religion **

jvc what year was the organizaion founded?
*September 5, 2012*

**english**

Imperative Interrogative Declarative Exclamatory 1.what a ball game this 2.Wear your boots in the rain. imperative
*September 4, 2012*

**health**

its B 80%
*August 11, 2012*

**chemistry **

If 3.20 kg of Sulphur reacts with oxygen, calculate the volume in millileters of sulphur dioxide gas formed at 30.5 degrees Celsius and 1.04 atm.
*June 9, 2012*

**Physics**

Volume of 1200 L of helium at 4000 Pa is heated from 45.0°C to 75.0°C increasing the pressure to 6000 Pa. What is the resulting volume of gas?
*April 11, 2012*

**Physics**

Given 435 in^3 of nitrogen at 1340psi (absolute) at 72.0°F. Find the volume at 1150psi at 45.0°F.
*April 11, 2012*

**Physics**

A welding tank has a gauge pressure of 2000psi at 40.0°F. What is the new gauge pressure if the temperature rises to 100°F?
*April 11, 2012*

**Physics**

Some air at 275 kPa absolute pressure occupies 50.0m^3. Find its absolute pressure if its volume is doubled at constant temperature.
*April 11, 2012*

**Physics**

Some propane occupies 150 cm^3 at 12.4°C. Find the temperature when its volume is 132ft^3 if the pressure remains constant.
*April 11, 2012*

**Physics**

Some hydrogen occupies 120 ft at 60.0°F. Find the temperature when its volume is 132ft^3 if the pressure remains constant.
*April 11, 2012*

**Chemistry**

1. Write a balanced equation : 2H^2O^2---O^2+ 2H^2O 2. Find the molar mass (g/mol) of each: 34.02 32.00 18.02 3. Divide grams water by the molar mass of water: .77g (1mol/18.02g) ~ .0427 mols 4. Use the mole ratios to find the number of hydrogen peroxide moles: 2H^2O^2---O^2+ ...
*April 10, 2012*

**math**

a jar contains 27 blue blocks 18 red blocks 12 orange blocks and 43 green blocks You put your hand in the jar and without looking pull out a block. About what fraction on the time would you expect to get a red block?
*April 10, 2012*

**Physics**

How many kcal of heat are required to vaporize 25.0kg of water at 100°C?
*April 2, 2012*

**Physics**

Find the increase in Volume of 50.0L of acetone when heated from 40.0°C to 75.5°C.
*April 2, 2012*

**Physics**

How many Btu of heat must be added to 900lbs of steel to raise its temperature from 20.0°F to 500°F? Specific heat of steel .115Btu/lb°F
*April 2, 2012*

**Physics**

A Brass rod 50.0 cm long expands 0.0734 cm when heated. Find the temperature change.
*April 2, 2012*

**Physics**

A 100 kg steam boiler is made of steel and contains 200 kg of water at 5.00°C. How much heat is required to raise the temperature of both the boiler and water to 100°C? The specific heat of Steel is 0.115kcal/kg°C. The specific heat of Water is 1.00kcal/kg°C
*April 2, 2012*

**math**

if you have a piece of string 11 ft. long and you cut it into 15 equal pieces how long will each piece be?
*February 13, 2012*

**Physics**

A ball is thrown horizontally from the top of a building 21.6 m high. The ball strikes the ground at a point 123 m from the base of the building. Find the x component of its velocity just before it strikes the ground. Find the y component of its velocity just before it strikes...
*February 4, 2012*

**Math**

Pamela and David walk on the same track. It takes Pamela 9 minutes and David 6 minutes to walk one lap. If they start walking at the same time, how many laps will each have walked when they cross the starting point together for the first time?
*February 1, 2012*

**math**

If I have a 66% in algebra Android we took a exam that's worth 20% of our grade Android I got a 54% on the multiple choice what would my average grade be?
*December 14, 2011*

**algebra 2nd grade**

10
*December 12, 2011*

**Career planning**

I chose D- All of the above
*December 6, 2011*

**Math**

I'm so lost.
*November 15, 2011*

**geometry**

Which of the following statements is true?Select one of the options below as your answer:A. A 25o angle is congruent to a 25o angle. B. Two intersecting lines form two pairs of congruent angles. C. It is possible for congruent angles to add up to 90o. D. All of the above are ...
*November 8, 2011*

**9th grade Biology**

4. After the temperature reaches 33 degrees Celcius, the rate of photosynthesis declines. Using knowledge of enzymes, explain why this happens. 6. As the amound of CO2 increases, what would happen to the rate of photosynthesis? And as the amount of CO2 increases, would the ...
*October 27, 2011*

**Algebra 2**

Find the coordinates of the vertices of the parallelogram with sides that are contained in the lines with equations y=3, y=7, y=2x, y=2x-13
*October 23, 2011*

**Math**

2989/7*2
*October 23, 2011*

**canyons,dunes,and deltas SCIENCE**

Weathering
*October 13, 2011*

**Physics**

A bicycle is moving at a constant speed of 12m/s as it covers a distance of 200m. it then applies its brakes and stops over the next 350m. how much time doe sthis total motion take?
*October 7, 2011*

**Math**

?? huh
*September 29, 2011*

**Math**

6 ways
*September 29, 2011*

**Geometry**

how do you solve using midpoint equation if you only have one pair of points? like to use midpoint equation you usually get two points (4,3) and (5,2) but ive been given only one point (3,1). how do i solve for midpoint with only one set of points? help please
*September 29, 2011*

**science**

What keeps proteins within the bilayer?
*September 27, 2011*

**chemistry 1 **

From data below, calculate the total heat (J) needed to convert 0.757 mol of gaseous ethanol (C2H6O) at 151°C and 1 atm to liquid ethanol at 25.0°C and 1 atm. Boiling point at 1 atm 78.5°C cgas 1.43 J/g·°C cliquid 2.45 J/g·°C ΔH°vap ...
*September 27, 2011*

**physics**

a quarterback throws a pass to a receiver. the release point for the football is 1.8 m above the ground. he projects the ball with a speed of 20 m/s at an angle of 40 above the horizontal. If the pass falls incomplete, how long is it in the air? If the pass falls incomplete, ...
*September 20, 2011*

**Math**

simplify 14/22
*August 18, 2011*

**Math**

simplify 64/76
*August 18, 2011*

**Math**

simplify 13/17
*August 18, 2011*

**Math**

Simplify -17/21.
*August 18, 2011*

**chemistry**

A piece of copper wire has a density of 8.9 g/cm3. What is the density of a chunk of copper that has a mass of 250 grams?
*June 25, 2011*

**geometry**

line segment AB and XY are congruent. if AB=5N-8 and XY= 2n+19 what is the legth of AB?
*June 22, 2011*

**chemistry**

what are some examples of suspensions?
*June 1, 2011*

**MATH**

20
*June 1, 2011*

**Chemistry**

Will you check this answer for me? the half-life of strontium-87 is 2.8hr. What percentage of this isotope will remain after 8 hours and 24 minutes? ?? 34%
*May 25, 2011*

**Pre-Calc**

A hall 200 feet in length is to be designed as an ellipse if the foci are 35 feet from the center. How high will the ceiling be from the center?
*May 11, 2011*