# J

Popular questions and responses by J-
## Wold History

Which of the following most directly resulted from the Neolithic Revolution? •Populations increased. •Complex cultures blended. •Religion became less important. 2. Which of the following best describes the emergence of social classes in early

*asked on September 13, 2016* -
## math-precalculus

A Ferris wheel is 50 meters in diameter and boarded from a platform that is 1 meters above the ground. The six o'clock position on the Ferris wheel is level with the loading platform. The wheel completes 1 full revolution in 6 minutes. How many minutes of

*asked on April 30, 2017* -
## Math Probabilities

A bag contains 9 red chips and 12 blue chips. Two chips are selected randomly without replacement from the bag. What is the probability that the two chips are the same color? That would be the probability of two reds PLUS the probability of two blues. The

*asked on March 6, 2007* -
## Physics

(a) How much charge does a battery have to supply to a 5.0 uF capacitor to create a potential difference of 1.5 V across its plates? How much energy is stored in the capacitor in this case? (b) How much charge would the batter have to supply to store 1.0 J

*asked on February 4, 2008* -
## Math

A 6 inch personal pizza has 630 calories, with 240 of those from fat. A 16 inch pizza is cut into 8 slices. Estimate the number of calories in one slice of a 16 inch pizza.

*asked on February 10, 2017* -
## physics

the motion of a particle along a straight line is described by the function x=(2t-3)^2 where x is in metres and t is in seconds. A)find the position ,veocity and acceleration at t=2 sec. B) find the velocity of the particle at origin.

*asked on June 26, 2012* -
## physics

A uniform metre rule of mass 90g is pivoted at the 40cm mark. If the rule is in equilibrium with an unknown mass m placed at the 10cm mark and a 72g mass at the 70cm mark,determine m.

*asked on November 11, 2017* -
## Math

Let x represent the number which shows up when a balanced die is rolled. Then x is a random variable with a uniform distribution. Let x-bar denote the mean of the numbers obtained when the die is rolled 32 times. For samples of size 32, which of the

*asked on April 22, 2007* -
## math-precalculus

Outside temperature over a day can be modeled as a sinusoidal function. Suppose you know the temperature varies between 73 and 87 degrees during the day and the average daily temperature first occurs at 8 AM. How many hours after midnight, to two decimal

*asked on April 27, 2017* -
## Chemistry

If you want to prepare 2.0 liters of a .25 M solution of NH4Cl, how many grams of the salt should you weigh out?

*asked on November 29, 2015* -
## Wold History

Having a hard time in World History! Please let me know if these are right and if not please tell me the answers! 1. How did the religious beliefs of the ancient Israelites differ from those of other nearby peoples? The Israelites believed in many gods,

*asked on September 22, 2016* -
## Biology

In an experiment, a researcher counts the number of oxygen bubbles produced by water plants placed under different colors of light. The researcher finds that water plants placed under white light release more oxygen bubbles than water plants placed under

*asked on July 27, 2014* -
## Physics

What is the thinnest film of a coating with n=1.42 on glass n=1.52 for which destructive interference of the red component (650 nm) of an incident white light beam in air can take place by reflection? I am confused on the n's and I have no idea what

*asked on April 21, 2008* -
## Chemistry

When normal atmospheric conditions are present, water is constantly being cycled between liquid and gaseous states by which of the following pairs of processes? A. Turgor pressure and filtration B. Melting point and condensation C. Evaporation and

*asked on July 27, 2014* -
## Physics

Coherent light of frequency 6.32 * 10^14 Hz passes through two thin slits and falls on a screen 85 cm away. You observe that the third bright fringe occurs at +- (plus or minus) 3.11 cm on either side of the central bright fringe. (a) How far apart are the

*asked on April 21, 2008* -
## Physics

Medical x rays are taken with electromagnetic waves having a wavelength around .1 nm. What are the frequency, period, and wave number of such waves? ok I got the frequency as 3 * 10^18 Hz and the wave number as 6.3 *10^10 rad/m but I can't seem to remember

*asked on March 31, 2008* -
## Physics

A wooden boxcar is moving along a straight railroad track at speed v1. A sniper fires a bullet (initial speed v2) at it from a high-powered rifle. The bullet passes though both lengthwise walls of the car, its entrance and exit holes being exactly opposite

*asked on September 18, 2010* -
## Math

The hypotenuse (side C) of a triangle is 13 inches long. Which of the following pairs of measurements could be correct for the lengths of the other two sides of the triangle? (Note: N + 82 =C2) A. 2.5 inches,4 inches B. 2.5 inches, 6 inches C.5inches,

*asked on July 22, 2014* -
## chemistry

Lithium metal dissolves in water to yield hydrogen gas and aqueous lithium hydroxide. What is the final concentration of hydroxide ions when 5.500 g of lithium metal is dropped into 750. mL of water?

*asked on October 4, 2010* -
## math

The diameters of ball bearings produced in a manufacturing process can be described using a uniform distribution over the interval 2.5 to 8.5 millimeters. What is the probability that a randomly selected ball bearing has a diameter less than 4.5

*asked on September 18, 2010* -
## Physics

A closely wound rectangular coil of 80 turns has dimensions of 25 cm by 40 cm. The plane of the coil is rotated from a position where it makes an angle of 37 degrees with a magnetic field of 1.10 T to a position perpendicular to the field. The rotation

*asked on March 3, 2008* -
## Physics

A transformer consists of 275 primary windings and 834 secondary windings. If the potential difference across the primary coil is 25 V, (a) What is the voltage across the secondary coil? (b) what is the effective load resistance of the secondary coil if it

*asked on March 18, 2008* -
## Physics

The internal resistance of a dry cell increases gradually with age, even though the cell is not used. The emf, however, remains fairly constant at 1.5 V. Dry cells must be tested for age at the time of purchase by connecting an ammeter directly across the

*asked on February 12, 2008* -
## Statistics

A card is drawn from a well shuffled deck of 52 cards. Find P (drawing an acre or a 9)

*asked on April 7, 2016* -
## Physics

Two small stereo speakers A and B that are 1.4 m apart are sending out sound of wavelength 34 cm in all directions and all in phase. A person at point P starts out equidistant from both speakers and walks so that he is always 1.5 m from speaker B. For what

*asked on April 21, 2008* -
## English

Which is a central idea from The Epic of Gilgamesh? A. Not all of the gods agree with Enlil’s plan to destroy humankind. B. Only some of the animals aboard the ship survive the flood. C. The captain of the ship was gifted with Utnapishtim’s

*asked on May 14, 2020* -
## math

The standard deviation of a sample taken from population A is 17.6 for a sample of 25. The standard deviation of a sample taken from population B is 21.2 for a sample of 30. The standard deviation of the sample mean differences is_____. (Round your answer

*asked on July 15, 2015* -
## physics

A wooden crate weighs 780 lb. What force is needed to start the crate sliding on a wooden floor when the coefficient of starting friction is 0.40?

*asked on February 22, 2013* -
## College Math

farmer wishes to fence a rectangular area along the river bank. No fence is required on the side adjacent to the river. The material for the fence costs P16.00 per meter for the side parallel to the river, P12.00 per meter for the side perpendicular to the

*asked on August 25, 2010* -
## calculus

Carbon-14 is a radioactive substance produced in the Earth's atmosphere and then absorbed by plants and animals on the surface of the earth. It has a half-life (the time it takes for half the amount of a sample to decay) of approximately 5730 years. Using

*asked on July 24, 2009* -
## Calculus

Evaluate exactly the value of the integral from negative 1 to 0 of the product of the cube of quantity 2 times x to the 5th power plus 6 times x and 5 times x to the 4th power plus 3, dx. Your work must include the use of substitution and the

*asked on April 20, 2019* -
## Math

It takes a hose 4 minutes to fill a rectangular aquarium 8 inches long, 9 inches wide, and 14 inches tall. How long will it take the same hose to fill an aquarium measuring 24 inches by 27 inches by 31 inches?

*asked on February 10, 2017* -
## Chem

joules needed to melt 30.0 g of ice at 0 ∘C and to warm the liquid to 60.0 ∘C so i did Q=mFf which i set up like 30.g x 334 j/c = 10020 J then i'm sorta confused what i'm doing next. explain in detail please?

*asked on February 15, 2016* -
## trig

Juana and Diego Gonzales, ages six and four respectively, own a strong and stubborn puppy named Corporal. It is so hard to take Corporal for a walk that they devise a scheme to use two leashes. If Juana pulls with a force of 23 lbs at an angle of 18° and

*asked on December 12, 2013* -
## Physics

You want to take a full length photo of your friend who is 2 m tall, using a 35 mm camera having a 50 mm lens. The image dimensions of 35 mm film is 24 mm by 36 mm, and you want to make this a vertical photo in which your friend's image completely fills

*asked on April 14, 2008* -
## Physics

A mirror on the passenger side of your car is convex and has a radius of curvature with magnitude 18 cm. (a)Another car is seen in this side mirror and is 13 m behind the mirror, if the car is 1.5 m tall, what is the height of its image? I can't figure

*asked on April 7, 2008* -
## math

In the standard (x,y) coordinate plane, the graph of (x + 3)2 + (y + 5)2 = 16 is a circle. What is the circumference of the circle, expressed in coordinate units?

*asked on August 14, 2013* -
## icp

Charge q is 1 unit of distance away from the source charge S. Charge p is six times further away. The force exerted between S and q is _____ the force exerted between S and p.

*asked on September 20, 2010* -
## organ chem

Why is thymol only slightly soluble in water, but very soluble in 1.0 M NaOH?

*asked on January 31, 2010* -
## Physics

A certain resistor has a resistance of 1.484 omega at 20 degrees celsius and a resistance of 1.512 omega at 34.0 degrees celsius. What is its temperature coefficient of resistivity? ok..I used a temperature equation but I can't get the right answer. so

*asked on February 4, 2008* -
## chemistry

50cm3 of hydrogen is collected over water at 17 degree celsius and 750 mm Hg pressure.Calculate the volume of dry gas at S.T.P.The water vapour pressure at 17 degree celsius is 14 mm Hg?

*asked on May 28, 2015* -
## Biology

Which of the following will happen if mRNA fails to be translated? A The cell's nucleus will produce more chromatin. B. Ribosomes will not be able to create protein. C. Mitochondria will release ATP. D. The cell will produce more mRNA I think it's B

*asked on July 27, 2014* -
## Math

There were 7 times as many marbles in Box A as in Box B. After Joyce transferred 294 marbles from Box A to Box B, both boxes had the same number of marbles. How man marbles were there in Box A at first.

*asked on November 20, 2013* -
## Physics

Find the forces exerted by the two supports of a 4.0m, 50-kg diving board when a 60-kg woman stands at its end. The two supports are 0.8m apart. This time consider the mass of the diving board.

*asked on June 24, 2012* -
## Physics

The crystalline lens of the human eye is a double convex lens made of material haveing an index of refraction of 1.44. Its focal length in air is about 8 mm which also varies. We shall assume that the radii of curvature of its two surfaces have the same

*asked on April 7, 2008* -
## Physics

When a solar flare erupts on the surface of the sun, how many minutes after it occurs does its light show up in an astronomer's telescope on earth? I am totally confused..help!

*asked on March 31, 2008* -
## Math

A triangular lot is 120ft on one side and has a property line of 700ft. Find the area of the lot in acres (figure not drawn to scale)

*asked on September 28, 2017* -
## Math

You need to buy some chicken for dinner tonight. You found an ad showing that the store across town has it on sale for $2.89 a pound, which is cheaper than your usual neighborhood store, which sells it for $2.99 a pound. Is it worth the extra drive? First,

*asked on February 10, 2017* -
## physics

two charges of equal magnitude are 25.5 cm apart if the force between the charges is 155 N what is the magnitude of the charges

*asked on April 28, 2015* -
## Biology

Which of the following is the purpose of valves in the venous circulatory system? A. Promoting movement of oxygenated blood toward the heart B. Facilitating stasis of blood in the veins C. Propelling blood through the vena cava D. Preventing backward flow

*asked on July 27, 2014* -
## Biology

Mutations during which of the following processes in animals will affect offspring of succeeding generations? A Meiosis B. Mitosis C. Translation D. Transcription I think A!

*asked on July 24, 2014* -
## PHYSICS

A) As a wind instrument warms up, the resonant frequencies of the instrument tend to slightly decrease. B) If the air in a concert hall warms up, the resonant frequencies of the string instruments will change precisely the same as the resonant frequencies

*asked on April 15, 2011* -
## Physics

A coil of wire with 200 circular turns of radius of 3 cm is in a uniform magnetic field along the axis of the coil. the coil has R=40 ohms. At what rate, in Teslas per second, must the magnetic field be changing to induce a current of .150 A in the coil? I

*asked on March 3, 2008* -
## Physics

A beam of protons is accelerated through a potential difference of 0.745 kV and then enters a uniform magnetic field traveling perpendicular to the field. (a) What magnitude of field is needed to bend these protons in a circular arc of diameter 1.75 m? (b)

*asked on February 25, 2008* -
## Physics

A 450 uF capacitor is charged to 295 V. Then a wire is connected between the plates. How many joules of thermal energy are produced as the capacitor discharges if all of the energy that was stored goes into heating the wire? I am totally confused I don't

*asked on February 4, 2008* -
## chemistry

if the amount of radioactive iodine-123 in a sample decreases from .400g to .100g in 26.2 hours, what is the half-life of iodine-123

*asked on April 18, 2013* -
## Physics

A certain digital camera having a lens with focal length 7.5 cm focuses on an object 1.85 m tall that is 4.25 m from the lens. (a) How far must the lens be from the photocells? (b) How tall is the image on the photocells? Is it erect or inverted? (c) A SLR

*asked on April 14, 2008* -
## Physics

We can reasonaly model a 75 W incandescent lightbulb as a sphere 6 cm in diameter. Typically, only about 5% of the energy goes to visible light; the rest goes largely to nonvisible infrared radiation. (a) What is the visible light intensity (in W/m^2) at

*asked on March 31, 2008* -
## physical science

Which description does the phrase "mechanical advantage" most closely relate to? A. The same amount of work using less force. B. The same amount of power using less work. C. The same amount of work using less power. D. The same amount of power using less

*asked on May 2, 2017* -
## Math

The land area of Statesville, NC, is 20.5 square miles. If the entire US population (currently about 320.2 million) were put inside the city limits of Statesville, determine the number of square feet that each person would have. Round your answer to two

*asked on February 10, 2017* -
## Biology

Which of the following classes of biomolecules are frequently responsible for bringing about cell differentiation? A Transcription factors B. lnterleukins C. Cytokines D. Nucleotidyl transferases I think it's A

*asked on July 27, 2014* -
## early childhood educastion

what can a teacher do to reinforce the primary relationship between the parent and child and communicate that the teacher does not desire to take the parent's place in the child's life?

*asked on April 24, 2014* -
## Bio

A______ is a tentative, testable explanation for an observed phenomenon. I am confused with hypothesis and theory. But my guess is hypothesis. is this true? or am I wrong?? thanks

*asked on November 28, 2013* -
## Chemistry

A coffee cup calorimeter contains 25.0 grams water at 23.8 C A 5.00g sample of an unknown metal at an initial temperature of 78.3 C was dropped into the calorimeter. The final temperature of mixture was 46.3 C. Calculate the specific heat of the metal. The

*asked on March 19, 2013* -
## Math?

How much money is one $100 bill plus $10 bills plus fifteen $1 bill?

*asked on February 20, 2013* -
## Calculus

explain why a scalar equation of the line exists in 2-D space, but not in 3-D space.

*asked on May 10, 2012* -
## Calculus

find lim f(x) - lim f(x) x->infinity x->-infinity if f(x)=ln (x+sqrt[x^2+a^2])/(x+sqrt[x^2+b^2]) a and b are real numbers

*asked on February 2, 2011* -
## physics pleaaaaaaaaaaaaaaaaaaaaaaaaaaaaaase I need

Consider a square ABCD of side 10cm and total mass 10kg. Let O be the center of the sqaure. We cut a square of corners O and C. Find the central mass of the obtained shape after removing the small cutten sqaure. I appreciate your help. thank you

*asked on January 6, 2011* -
## Statistics

Question 1 Use the following research question and data for questions 1 - 6. A researcher is examining the effects of a computer-based training program designed to teach algebra. The researcher randomly selects subjects for two groups and gives one group

*asked on October 18, 2008* -
## Physics

A certain digital camera having a lens with focal length 7.5 cm focuses on an object 1.85 m tall that is 4.25 m from the lens. (a) How far must the lens be from the photocells? (b) How tall is the image on the photocells? Is it erect or inverted? (c) A SLR

*asked on April 14, 2008* -
## physics

A neutral conductor completely encloses a hole inside of it. You observe the outer surface of this conductor carries a charge of -12 uC. (a) Can you conclude that there is a charge inside the hole? If so, what is the charge? (b) How much charge is on the

*asked on January 28, 2008* -
## physics

You place a point charge q = -4.00 nC a distance of 9.00 cm from an infinitely long, thin wire that has linear charge density 3.00×10−9C/m. What is the magnitude of the electric force that the wire exerts on the point charge?

*asked on April 10, 2020* -
## Math

Jerome has 1/4 of the groups video games at his house. Mario has 2/5 of the groups video games at his house. What fraction of video the groups video games is either at Jerome's house or Mario's house?

*asked on December 8, 2017* -
## Us government

19. How is Snyder v Phelps an example of competing rights? Be specific in your answer. The court case of Snyder v phelps is an example of competing rights because the rights of privacy and speech are making distress and this came into conflict with the

*asked on November 18, 2017* -
## math

A parking garage has floors above and below ground level. For a scavenger hunt, galas friends are given a list of objects they need to find on the third floor and fourth level below ground, the first and fourth above ground, and ground level. a. If ground

*asked on October 10, 2017* -
## Chemistry

Determine the mass of NH2CH2CO2Na and the volume of 0.150 M HCl solution required to make 1.35 L of a buffer solution at pH=10.75 and at a total concentration of 0.33 M. pKa(NH2CH2CO2H)=9.88. a.Mass of NH2CH2CO2Na: b. Volume of HCl solution: Hi Im sooo

*asked on November 16, 2016* -
## Chemistry

Give a simple test that would allow you to distinguis between the following pairs of anions. Tell what you would do and what you should observe for each anion. A. CO3^2- and SO4^2- B. Cl- and SO4- C. CO3^2- and Cl- Now, for each cation A. B^3+ and Ca2+ B.

*asked on November 15, 2016* -
## Chemistry

For a 0.47 M solution of LiClO compute the pH. Hi. I am confused about this question. I calculated the pH...but my answer is wrong. what am I doing wrong??? pH=-log(0.47) pH=0.33

*asked on November 13, 2016* -
## precalc

Solve in radians. 1) sin2X = 1/2 2) tan2 (X + pi/2) = 1 3) 5 - 3sec (X - pi/4) = -1

*asked on October 27, 2015* -
## Art and Creative Development

Young children who learn easily, ask thought-provoking questions, and are very curious are often: A. gifted or talented B. behavior problems in the classroom C. poor at following directions D. overly shy and withdrawn socially i think it is between a and d

*asked on May 4, 2015* -
## English

what is the focus of the novel of the great gatsby, whats the writers styles, and his views and tone toward the subject (even if it is himself)

*asked on October 3, 2014* -
## Pre-Calc (Circles). Please help :(

Five concentric circles with radii 1, 2, 3, 4, and 5 are drawn as shown dividing the circle of radius 5 into five regions: a circle of radius 1 and 4 annuuli (rings). What is the probability that a point chosen randomly from within the circle of radius 5

*asked on September 28, 2014* -
## business

Old Navy executives want to target an older crowd in order to increase the firm?s market share so they survey men and women ages 40 to 60 about how often and for what type of activities they wear casual clothing. This is an example of reliability

*asked on September 13, 2014* -
## Life Science

Less-economically developed countries will experience higher birth rates than more-economically developed countries due to A. decreased availability of sanitary water. B. higher infant mortality rate. C. higher literacy rate of women. D. increased

*asked on July 26, 2014* -
## Math

A, B, C, and D are points on a line, and the lengths of the line segments are: AB = 12, BC = 4, CD = 7, and DA = 15. Which of the following is a possible order for the points? A.A,B,C,D B. A,C,D,B C. A,D,C,B D. A,C,B,D

*asked on July 22, 2014* -
## physics/calc

An anchor weighing 110 lb in water is attached to a chain weighing 2 lb/ft in water. Find the work done to haul the anchor and chain to the surface of the water from a depth of 35 ft.

*asked on March 21, 2014* -
## math

a cube with 2 in sides is placed on a cube with 3 in sides. then a cube with 1 in sides is placed on the 2 in cube. what is the surface area of the three cube tower?

*asked on March 21, 2013* -
## orgo

A sample of naphthalene, which should be pure white, was found to have a grayish color after the usual purification procedure. The melting point was correct, and the melting point range was small. Explain the gray color.

*asked on January 30, 2013* -
## Calculus

Three forces of 5 N, 8 N, and 10 N act from the corner of a cube along its edges. Using Cartesian vectors, find the magnitude of the resultant force.

*asked on May 7, 2012* -
## Calculus

Explain why a line in three-space cannot be represented by a scalar equation.

*asked on May 5, 2012* -
## Science

When plants die, what happen to carbon dioxide? They would be more co2 or less?

*asked on October 18, 2011* -
## history

Who were some of the original Texas Wildcatters?

*asked on January 6, 2011* -
## math/ physics

Consider a square ABCD of side 10cm and total mass 10kg. Let O be the center of the sqaure. We cut a square of corners O and C. Find the central mass of the obtained shape after removing the small cutten sqaure. I would appreciate your help. thank you

*asked on January 6, 2011* -
## College Physics

a horizontal speed of 15.8 m/s and a vertical speed 10.0 m/s upward. What is the vertical speed 1.12 s later?

*asked on September 26, 2010* -
## spanish

Que te gusta hacer? Will someone give me some possible answers for this question?

*asked on September 15, 2010* -
## geometry

Two angles are supplementary. They have measures of (7x+2) and (3x-2), respectively. What is the value of x?

*asked on February 18, 2010* -
## AP Physics

While two forces act on it, a particle is to move at the constant velocity v = (3 m/s) i - (4 m/s) j. One of the forces is F1 = (2 N) i + (- 6 N) j. What is the other force? ( _____ N) i + ( _____ N) j Only two horizontal forces act on a 3.0 kg body that

*asked on November 13, 2008* -
## CHEMISTRY

I've been trying to do this problem but I would get confused and stuck.. Consider a sample of a hydrocarbon at 0.959 atm and 298 K. Upon combustion the entire sample in oxygen, you collect a mixture of gaseous carbon dioxide and water vapor at 1.51 atm and

*asked on November 7, 2008* -
## physics

Calculate the energy released in the fusion reaction 2 3 4 1 1 H + 1 H->2 H +0 n. The atomic mass of 3 1 H (tritium is 3.016049 u. I am lost! help please!

*asked on May 5, 2008* -
## physics

A parallel plate capacitor having plates 6.0 cm apart is connected across the terminals of a 12.0 V battery. (a) Being as quantitative as you can, describe the location and shape of the equipotential surface that is at a potential of +6.0 V relative to the

*asked on January 28, 2008*