Friday

May 6, 2016
Total # Posts: 815

**math**

a board of 4 members is going to be formed from the 30 students of a class. The board is formed of a president a vice president a secretary and a treasurer. What is the number of possible boards knowing that each of the 30 students can occupy any post?
*April 24, 2016*

**math**

four girls bought each a swimsuit and decided to borrow among themselves. How many possible ways can they dress up knowing that each girl can use the same swimsuit only once?
*April 24, 2016*

**math(counting)**

an anagram of a word is obtained by permuting its letters. a-how many anagrams does the word "MAIRE" have b-Same question for the word "OISEAU"
*April 24, 2016*

**math(counting)**

in how many different ways can 3 boys and 2 girls sit on a bench? in how many different ways can they sit knowing that the boys have to sit near each other and the girls also
*April 24, 2016*

**Math**

I don't know
*April 20, 2016*

**Geometry- PLEASE HELP!!**

Point $G$ is the midpoint of median $\overline{XM}$ of $\triangle XYZ$. Point $H$ is the midpoint of $\overline{XY}$, and point $T$ is the intersection of $\overline{HM}$ and $\overline{YG}$. Find the area of $\triangle MTG$ if $[XYZ] =150$.
*April 19, 2016*

**Geometry**

Altitudes $\overline{XD}$ and $\overline{YE}$ of acute triangle $\triangle XYZ$ intersect at point $H$. If the altitudes intersect at a $123^\circ$ angle, and $\angle YXH = 26^\circ$, then what is $\angle HZX$ in degrees?
*April 19, 2016*

**Math **

Points J and K, plotted on the coordinate grid, are two vertices of rectangle JKLM. Rectangle JKLM has an area of 7 square units. Point J is located at (2, 1) and point K is located at (-5, 1). Each vertex of the rectangle is located at a point that has integer coordinates.
*April 11, 2016*

**Algebra**

AAAAAAAhhHHHH I need a answer too
*April 7, 2016*

**stas**

find the probability of correctly answering the first 2 questions on a multiple choice test if random guesses are made and each question has six possible answers
*April 4, 2016*

**English**

*than
*March 30, 2016*

**English**

#1 means it took him 5 days to read the book. In other words. He finished the book in 5 days. #2 means he waited 5 days to START reading the book. It doesn't mean he finished reading the book from what I can tell. #3 probably means he finished reading the book in LESS Than...
*March 30, 2016*

**Science**

The force in the horizontal direction doesn't affect the mass. You would need to know the force of gravity (in newtons) on the box and the acceleration of gravity which is 9.8m/s^2 on Earth.
*March 30, 2016*

**Algebra 2**

Q: What represents the sum of a geometric series with 8 terms whose first term is 3 and common ratio is 4. A: 65,535 Is my answer right? I wasn't sure when adding up the terms versus using Sigma notation.
*March 7, 2016*

**science fair **

will a heavy metal spring launch a baseball 7 feet in the air with 5 pounds of preasure
*March 6, 2016*

**Chemistry**

A 3.50L balloon contains 0.178 mol of gas. If 0.094 mol of gas is added to the balloon, what will be the new volume?
*March 2, 2016*

**physics**

A rocket blasts off from rest and attains a speed of 49 m/s in 16 s. An astronaut has a mass of 56.3 kg. What is the astronaut's apparent weight during take off?
*February 8, 2016*

**Physics**

A 1000-kg aircraft going 25 m/s collides with a 1500-kg aircraft that is parked. They stick together after the collision and are moving at 10 m/s. If they skid for 30 seconds before stopping, how far (in meters) did they skid? Hint: Are the aircraft moving at a constant ...
*January 30, 2016*

**Chemistry**

9.299 grams
*January 26, 2016*

**Chemistry**

Molar mass of H2O = 18.0 g/mol 18 g ------> 6.02x10^23 atoms g -------> 3.11x10^23 atoms ( 3.11x10^23) * 18 / 6.02x10^23 5.598x10^24 / 6.02x10^23 = 9.299 gramas hope thi helps!.
*January 26, 2016*

**Chemistry**

Percent of gas (C2H2 ) formed.
*January 26, 2016*

**Chemistry**

What is the percentage of gas (C2H2) formed when 2.66g of calcium carbide (CaC2) reacts completely with 50g water?
*January 26, 2016*

**math**

how long would it take a car traveling 175 mph to go 26 miles?
*January 24, 2016*

**Chemistry**

Calculate the equilibrium constant for the equilibrium knowing that there are 2 moles of O2 H2, 6 moles of O2 and 3 moles of H2O in a jar reactor 2L? 2 H2 + O2 = 2 H2O
*January 21, 2016*

**Algebra**

Nevermind guys, I solved it. For future strugglers: equation A: 3a+12s=262.5 equation B: 4a+8s=230 multiply equation B so that a variable can be negated when you add the two equations together. In this case I chose variable (S) so i multiplied equation B by -1.5 so that -3a=-...
*January 19, 2016*

**Algebra**

Math club purchased 3 adult tickets and 12 student tickets for $262.50. Physics club purchased 4 adult tickets and 8 student tickets for $230.00. How much do the adult and student tickets cost?
*January 19, 2016*

**Maths**

The nth term and the sum of n terms of a geometric sequence are 5 and 55 respectively. If the commom ratio is -(1/2)n find the first term and value of n
*January 13, 2016*

**Math**

If a person throws 3 darts at a dartboard, how many possible combinations are there to get a sum of 34?
*January 5, 2016*

**Physics **

A baseball player hits a home run over the left-field fence, which is 104 m from home plate. The ball is hit at a point 1.08 m directly above home plate, with an initial velocity directed 35.0° above the horizontal. By what distance does the baseball clear the 3.00 m high ...
*December 8, 2015*

**US History**

probaly england
*December 2, 2015*

**math**

how much dose 1 cup of sugar cost?
*December 2, 2015*

**Chemestry**

Iron metal reacts with oxygen gas to form rust, iron (III) oxide. Which of the following correctly shows the balanced equation for this reaction?
*December 2, 2015*

**math help pls pls**

the answer is sometimes i recommend you google it first
*December 2, 2015*

**Calculus**

The amount remaining of a radioactive substance after t hours is given by A(t) = 100ekt. After 12 hours, the initial amount has decreased by 4%. How much remains after 48 hours? What is the half-life of the substance?
*November 23, 2015*

**Physics**

Damon, Where do you suggest I look for an approximate mph figure. I realize we are ignoring key factors, but surely someone can give me an educated guess - - e.g. the body would hit the ground at 100 mph plus or minus 10 mph. Thanks
*November 20, 2015*

**Physics**

A 180 pound body is dropped from a helicopter 5 miles (26400 ft.) up - - what maximum speed would the body attain, in miles per hour, before hitting the ground? Disregard gravity, air density, etc. factors, a very rough approximation is all that is needed. Thanks.
*November 20, 2015*

**Physics**

If a 180 pound body is dropped from an airplane 5 miles (26400 ft.) up: a/ how long would it take for the body to reach the ground? b/ what would be the maximum speed the body would attain in miles per hour? Close approximations are all that are required here. Thanks.
*November 20, 2015*

**Physics**

If a 180 pound body was dropped from a plane 5 miles in the air - how long would it take for the body to reach the ground?
*November 19, 2015*

**math**

Independent random samples, each containing 800 observations, were selected from two binomial populations. The samples from populations 1 and 2 produced 320 and 400 successes, respectively. Construct a 90% confidence interval for the true difference in population proportions ...
*November 18, 2015*

**math**

Suppose x has a binomial probability distribution with n = 200 and p = 0.60. Use the normal approximation to the binomial to find P (X > 130).
*November 18, 2015*

**Physics**

The instruments attached to a balloon have a mass of 5kg. The balloon is released and exerts an upward force of 100 N. After the balloon has accelerated for 10s, the instruments are released. What is the velocity of the instruments at the moment of release?
*November 2, 2015*

**Physics**

The driver of a car is going 90 km/hr suddenly sees a barrier40m ahead. It takes the driver .75 sec to apply the brakes, and the average acceleration during braking is -10m/s^2. Will the car hit the barrier and use calculation to show work.
*October 31, 2015*

**Physics**

10.234234
*October 29, 2015*

**Trig**

mercury rotates around the sun in approx. 89 earth days (or 7,689,600 s. use a calculator to approximate its angular speed. choices: 4.09x10^-7 0.035 0.071 8.17x10^-7
*October 21, 2015*

**Did you read The Pig Man And Me**

John Quinn does not explain the rule about the paddle to Paul, the narrator of “The Pigman & Me.” How does this one action affect the rest of the essay?
*October 11, 2015*

**HELP SCIENCE ASAP**

How are fish, amphibians, reptiles, and birds alike? How are they different? Include at least two similarities and two differences.
*October 7, 2015*

**ela**

Which section of a personal narrative requires the most development? a. introduction b. conclusion c. character introduction d. plot my answer is a can you check it for me
*October 5, 2015*

**ELA HELP FAST**

Which section of a personal narrative requires the most development? a. introduction b. conclusion c. character introduction d. plot
*October 5, 2015*

**Social Studies**

what do you mean
*October 5, 2015*

**Social Studies**

What examples are given of a limited government and an unlimited government in the section? How did each type of government affect its citizens? Japans government
*October 5, 2015*

**History**

Its fine i got my dad to help me. Thank you
*September 13, 2015*

**History**

"The renewable energies roadmap unveiled earlier this month by the Commission sets a target of 20% for the share of total energy supply to come from renewable sources. “It is not the first time that targets for renewable energy have been fixed. In 1997, the European ...
*September 13, 2015*

**psychology**

Dr. Jefferson is conducting an experiment in which she is interested in the effects of caffeine on visuospatial ability in adult participants. She conducts an experiment in which she gives one group a pill containing 20mg of caffeine and a second group a placebo pill. One hour...
*September 13, 2015*

**Psychology**

A researcher has conducted an experiment in which she has given participants a placebo, 10mg, and 20mg of a drug. She then measured their anxiety, blood pressure, and heart rate in response to the drug. How many levels does this experiment’s independent variable have?
*September 13, 2015*

**Psy 326**

We use _______________ to communicate the patterns and distribution of our measured variables.
*August 24, 2015*

**physics**

A bird watcher meanders through the woods, walking 0.744 km due east, 0.925 km due south, and 3.97 km in a direction 18.3 ° north of west. The time required for this trip is 1.765 h. Determine the magnitudes of the bird watcher's (a) displacement and (b) average ...
*August 14, 2015*

**Physics**

Knowing that you have the mass of each sun, M1=M2=M which is 2x10^30 kg, and you have the distance between the two stars a=1 AU, you can use Kepler's third law to solve for the period in seconds: p^2=((4pi)^2(a)^3)/(Gm) where p is measured in seconds, a is measured in ...
*August 14, 2015*

**physics**

A bird watcher meanders through the woods, walking 0.544 km due east, 0.925 km due south, and 3.58 km in a direction 17.3 ° north of west. The time required for this trip is 1.957 h. Determine the magnitudes of the bird watcher's (a) displacement and (b) average velocity.
*August 12, 2015*

**Langauge Please Help**

The novel to kill a mockingbird feature a main character named scout. Scout is also the voice that tells the story. What point of view is used in the novel? A.First Person B.Third-Person Limited<----------- C.Third-Person Omniscient The prefix a- can mean "none" ...
*August 11, 2015*

**Math**

A ball is thrown, and its height is recorded a number of different times. The ball reaches a maximum height of 20 m after 1.5 s. How do you sketch this relation from just a vertex. Grade 11 functions
*July 18, 2015*

**Math- algebra **

An experiment stain of bacteria is being used to treat an oil spill. A colony of 2^13 cells will be sufficient to ocean up the spill. If the colony is started with a single cell, and cells increase in number by splitting every 15 minutes, in how many hours will the colony ...
*June 5, 2015*

**college math**

You are a moron
*May 13, 2015*

**Math**

430
*May 5, 2015*

**Algebra 2**

An object is moving at a speed of 3 + 2 𝑓𝑡/𝑠. How long would it take the object to travel 20 𝑓𝑡? [looking for actual solution and not decimal approximation]
*May 1, 2015*

**Chemistry physics**

3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge
*March 31, 2015*

**Physics**

If 3.25x10-3 kg of gold is deposited onto the negative electrode of an electrolytic cell in a period of 2.78 hours, what is the current through this cell in amperes? Assume that the gold ions carry one elementary unit of charge
*March 31, 2015*

**Math**

Would it be 122?
*March 15, 2015*

**Math**

If the standard error of measurement is 3, and a person scores 125, Standard error of measurement with one standard deviation would put the score at ____?
*March 15, 2015*

**math**

A rectangular piece of carpet is place on the floor of a rectangular room leaving a margin of 1 m around it. If the room measures 8 m by 6 m find the area of the room not covered by the carpet.
*March 10, 2015*

**Physics**

Carl hits a 0.05 kg golf ball giving it a speed of 65 m/s. What impulse does he impact to the ball?
*March 6, 2015*

**Calculus (Partial Derivatives)**

A car dealer determines that if gasoline-electric hybrid automobiles are sold for x dollars apiece and the price of gasoline is y cents per gallon, then approximately H hybrid cars will be sold each year, where H(x,y)=6000−13x^(1/2)+2(0.1y+20)^(3/2). She estimates that t...
*March 4, 2015*

**Calculus (Partial Derivatives)**

A car dealer determines that if gasoline-electric hybrid automobiles are sold for x dollars apiece and the price of gasoline is y cents per gallon, then approximately H hybrid cars will be sold each year, where H(x,y)=6000−13x^(1/2)+2(0.1y+20)^(3/2). She estimates that ...
*February 28, 2015*

**Calculus (Partial Derivatives)**

It's supposed to be Q(x,y)=40xy^(1/5)
*February 28, 2015*

**Calculus (Partial Derivatives)**

Using x hours of skilled labor and y hours of unskilled labor, a manufacturer can produce Q(x,y)=40xy1/5 units each week. Currently 20 hours of skilled labor and 243 hours of unskilled labor are being used. Suppose the manufacturer reduces the skilled labor level by 2 hours ...
*February 28, 2015*

**Economics**

1. How does the current anti-corruption movement in China affect relatively tax free countries(ex. monocao, switerland etc.)? 2. EU relation with China
*February 26, 2015*

**physics**

Two horizontal forces, and , are acting on a box, but only is shown in the drawing. can point either to the right or to the left. The box moves only along the x axis. There is no friction between the box and the surface. Suppose that = +8.3 N and the mass of the box is 4.5 kg...
*February 19, 2015*

**Calculus**

Since it's compunded continuously, you use Present Value = Integrate from 0-T f(t)e^(-rt). It doesn't give a time limit, so we'll assume it's infinte. Integrate from 0-Infinity 110e^(-.08t) =[-1375e^-.08(Inifinity)]-[-135e^-.08(0)] = 0-(-1375) = 1375
*February 13, 2015*

**Chemistry**

calculate the density of NH3 at S650mm of Hg
*February 11, 2015*

**Bobpursley**

Look at my problem again please thanks
*February 5, 2015*

**Physics**

The spring force should be 588 N/m and velocity 0.700 m/s
*February 5, 2015*

**Physics**

3 kg object is fastened to a light spring with the intervening cord passing over a pulley. The pulley is frictionless and it's inertia may been neglected. The object is released from rest when the spring is unstretched. If the object drops 10 cm before stopping find the ...
*February 5, 2015*

**physics**

Why no one answer me
*January 20, 2015*

**physics**

You set your stationary bike on a high 80 N friction like resistive force and cycle for 30 min at speed of 8 m/s. Your body is 10% efficient at converting chemical energy in your body into mechanical work. What is your internal chemical energy change? How long must you bike to...
*January 20, 2015*

**physics**

A fire engine must lift 30 kg of water a vertical distance of 20 m each second. What is the amount of power needed for the water pump for this fire hose? P=W/t=Fd/t=mgd/t (30)(9.8)(20)/1= 5880 W is that right?
*January 20, 2015*

**physics**

A 75 kg bobsled is pushed along a horizontal surface by two athletes. After the bobsled is pushed a distance of 4.5 m starting from an initial speed of 1.2 m/s, its speed is 6.0 m/s. What is the change in kinetic energy? Find the magnitude of the net force on the bobsled.
*December 15, 2014*

**physics**

A student wearing frictionless in-line skates on a horizontal surface is pushed, from rest, by a friend with a constant force of 45 N. How far must the student be pushed, starting from rest, so that her final kinetic energy is 352 J?
*December 15, 2014*

**physics**

How much work is required to accelerate a 0.145 kg baseball from rest, to a speed of 38.7 m/s?
*December 15, 2014*

**Calculus**

Is 72 the correct answer?
*December 7, 2014*

**Calculus**

Find the area of the region bounded by the curves y=12-x^2 and y=x^2-6. Hint:The answer should be a whole number.
*December 7, 2014*

**Chemistry (Titrations)**

In order to standardize a KMnO4 solution, 0.2848 g Fe(NH4)2(SO4)2·6H2O was dissolved in 25 mL 0.18 M H2SO4. The KMnO4 solution was added to the Fe(NH4)2(SO4)2·6H2O solution until a pale pink color persisted. The titration took 24.2 mL of KMnO4 solution. What is ...
*November 30, 2014*

**business statistics**

10.55 Consider an experiment with four groups, with eight values in each. For the ANOVA summary table below, fill in all the missing results: Source Degrees of Freedom Sum of Squares Mean Square (Variance) F Among groups c - 1 = ? SSA = ? MSA = 80 FSTAT = ? Within groups n - c...
*November 27, 2014*

**Math**

how to write 4(x+2)+3x+2(x-y) in the distribt. property form
*November 23, 2014*

**Chemistry**

Calculate the pH of a 1.19M sodium formate, HCOONa, solution.
*November 23, 2014*

**Chemistry**

Calculate the pH of a buffer solution made by mixing 231 mL of a 1.04M trimethylamine (CH3)3N solution with 176 mL of a 1.38M trimethylammonia chloride, (CH3)3NHCl solution. Enter your answer to TWO decimal places. DO NOT use scientific notation.
*November 23, 2014*

**Chemistry**

How many grams of nitric acid (HNO3) must be dissolved in 590 ml of water to make a solution with a pOH = 10.1? Select one: a. 2.9 x 10-9 g b. 7.9 x 10-3 g c. 4.7 x 10-3 g d. 7.9 x 10-6 g e. 7.4 x 10-5 g
*November 23, 2014*

**physics**

A bee flies to a flower 583 m due south of its hive. The bee’s speed in still air is 0.68 m/s, and there is a wind blowing toward the south at 0.16 m/s. How long will it take the bee to travel to the flower and back to the hive? Answer in units of s
*November 18, 2014*

**Chemistry (Acid&Base)**

How many mL of 0.203 M HCl(aq) are required to prepare a diluted solution that has a concentration of 0.0433 M in a 100-mL volumetric flask?
*November 16, 2014*

**Chemistry**

Consider the reaction 2 SO2(g) + O2(g) in equilibrium with 2 SO3(g) . At 25°C delta H° = -197.78 kJ and delta S° = -187.95 J/K. Using this information, calculate the equilibrium constant for the reaction at -32°C. (R = 8.314 J/K) Enter your answer using TWO ...
*November 16, 2014*

**statistics**

It seems that people are choosing or finding it necessary to work later in life. Random samples of 200 men and 200 women age 65 or older were selected, and 80 men and 59 women were found to be working. At á = 0.01, can it be concluded that the proportions are different
*November 15, 2014*