# Elena

Most popular questions and responses by Elena-
## Science help! URGENT. Check answers

1. True or False? A model train traveling at a constant speed around a circular track has a constant velocity. (False) 2.Which of the following would be affected if a soaring eagle changed direction but remained at a constant speed? acceleration only

*asked on October 15, 2013* -
## Science help! URGENT. Check answers

1. True or False: If the net force of an object is 0 N, the forces are considered unbalanced. (True) 2. Which of the following forces causes a feather to fall slower than a blowing ball? gravity ← rolling friction sliding friction air resistance 3. A

*asked on October 21, 2013* -
## university chemistry

The instruction booklet for your pressure cooker indicates that its highest setting is 11.4 psi. You know that standard atmospheric pressure is 14.7 psi, so the booklet must mean 11.4 psi above atmospheric pressure. At what temperature will your food cook

*asked on January 31, 2010* -
## Science. Check answers

1. True or False: If the net force of an object is 0 N, the forces are considered unbalanced. (True) 2. Which of the following forces causes a feather to fall slower than a blowing ball? gravity ← rolling friction sliding friction air resistance 3. A

*asked on October 21, 2013* -
## physic

The amplitude of an oscillator decreases to 36.2% of its initial value in 20.5 s. What is the value of the time constant?

*asked on December 5, 2009* -
## Math Help? Check my answers.

1. r/5 = 9/21 r = 9 r = 2.14 r = 11.66 r = 37.8 2. A recipe calls for 3 cups of flour to make 3 dozen cookies. Use the proportion to calculate how much flour is needed to make 9 dozen cookies. 3cups/3dozen = xcups/9dozen 6 cups 3.5 cups 9 cups 12 cups 3.

*asked on November 5, 2013* -
## chemistry

Use activity coefficients to find the concentration of hydrogen ions in a solution of 90.0 mM butanoic acid and 0.05 M NaCl. The ionization constant of butanoic acid is Ka = 1.52 × 10-5. Take the size of C3H7COO– to be 500 pm. How do I calculate the

*asked on October 3, 2014* -
## MATH

explain how to construct a perpendicular bisector

*asked on March 12, 2014* -
## math

You and 4 friends go to a concert. In how many different ways can you sit in the assigned seats? 20 24 48 120 I think its A im not to sure

*asked on March 5, 2019* -
## Science

the process in which body cells are duplicated in order to grow and repair body tissues is called

*asked on March 6, 2014* -
## Algebra 1

Which statement best demonstrates why the following is a non-example of a polynomial? 33/16 - 62y^2xz-35z^1/3y^2 a. The expression has a variable raised to a negative exponent. b. The expression has a variable in the denominator of a fraction. ** c. The

*asked on March 30, 2016* -
## Physics- Help!!

1. What is the heat required in kilocalories to convert 2 kg of ice at 0°C completely into steam at 100°C? (I thought it was 2000 kilo cals but I think I'm wrong??) a. 80 Calories b. 1440 Calories c. 4186 Calories d. 540 Calories 2. A gaseous refrigerant

*asked on December 20, 2015* -
## 7 grade math

Consider two types of nonlinear equations. What unique quality does each possess and how does that quality cause the graph's unique shape? Name two unique examples of these shapes in real-world situations.

*asked on May 27, 2014* -
## math

In triangle wxy, wy is congruent to xy. the perimeter of triangle wxy is 76 inches. how many inches long is wx?

*asked on June 22, 2016* -
## Language Arts

Which sentence has correct subject - verb agreement a) casey or robbie are coming to the movies with us b) swimming and skiing is my favorite sports c) sandwhiches or pizza both sounds good for a quick dinner** d) either your brother or his friend is

*asked on March 2, 2016* -
## english

In "A Man Called Horse," After his wife leaves him, Yellow Robe Behaves recklessly in battle because he A. would rather die than live with the bitterness he feels as a result of his lost pride B. is trying to gain membership in the society known as the

*asked on May 28, 2014* -
## Trigonometry

find sin2x, cos2x, and tan2x if sinx= -2/sqrt 5 and x terminates in quadrant III

*asked on March 25, 2014* -
## Language Arts

Under a spreading chestnut tree which syllables are unstressed?

*asked on March 10, 2016* -
## Science

What mass of sodium has the same number of atoms as 50.0 g of calcium?

*asked on March 7, 2017* -
## math

If Jim is twice as old as Jerry plus six, Jerry is three years older than Tom, and Tom is 12, how old is Jim? I got = Jim is 36

*asked on January 14, 2015* -
## Algebra

The distance required for an emergency stop for a car varies directly as the square of the car’s speed. A car traveling at 50 mph requires 140 feet to stop. What is the stopping distance for a car traveling at 30 mph? What is the stopping distance for a

*asked on October 22, 2011* -
## Algebra I math

Which statement best demonstrates why the following is a non-example of a polynomial? 33/16 - 62y^2xz-35z^1/3y^2 a. The expression has a variable raised to a negative exponent. b. The expression has a variable in the denominator of a fraction. c. The

*asked on March 30, 2016* -
## math

Does a machine that takes one quarter at a time into its input and produces one gumball in its output act like a function? my guess is YES

*asked on February 3, 2015* -
## architecture

Describe the differences you observe between the art and architecture of the Early Renaissance (Chapter 8) and that of the High and Late Renaissance. Select an Early Renaissance work of painting, sculpture, and architecture, and compare them to examples

*asked on February 5, 2013* -
## math

Does the Commutative Property apply to this situation? I ate dinner and read a book. I got = Yes.

*asked on January 14, 2015* -
## math

An elementary school collected a total of 240 cans during a food drive. Grade 3 students collected 1/3 of all the cans grade 4 students collected 52 cans, and the rest of the cans were collected by grade 5 students. How many cans did grade 5 collect? A.28

*asked on March 29, 2013* -
## Math

Christine currently has $5000 in her 401(k) and plans to contribute $100 each month for the next 30 years into it. What will be the value of Christine's 402(k) in 30 years if the per annum rate of return is assumed to be 12% compounded monthly?

*asked on December 10, 2012* -
## math

i am a number in the fourth row on the hundred chart. my ones digit is twice my tens digit. what number am i;

*asked on September 19, 2010* -
## physic

he current in a 100 watt lightbulb is 0.840 A. The filament inside the bulb is 0.140 mm in diameter. a) What is the current density in the filament? b) What is the electron current in the filament?

*asked on March 26, 2010* -
## Science

Match the question with the correct conversion factor needed. Column A 1.What is the mass, in grams, of a single atom of carbon?: 2.What is the mass, in grams, of a single atom of iron?: 3.What is the mass, in grams, of a single molecule of water?: 4.What

*asked on March 7, 2017* -
## Math

One fourth of a watermelon is divided among three friends what fraction of the whole watermelon will each person get

*asked on January 25, 2017* -
## Physics

An object is placed 11 cm in front of a concave mirror whose focal length is 23 cm. The object is 3.6 cm tall. Determine (a) the location of the image, taking a real image as a positive value and a virtual image as a negative value. (b) Determine the

*asked on April 11, 2013* -
## Math

Perform the indicated operations. Reduce the answers to lowest terms.... 1.) 7 3/5 + 2 4/7 = _______________ 2.) 8 5/9 + 15 5/6 =________________ 3.) 14 5/10 + 8 3/5 = ________________ 4.) 5/6 x 3/4 = _____________________ Reduce each fraction to lowest

*asked on January 10, 2013* -
## Science

3 elements that have the same properties most like Helium

*asked on September 14, 2010* -
## chemistry

what are the possible sources of error that might lead to an erroneous determination of the concentration of the acetic acid in the titration lab?

*asked on January 31, 2010* -
## Chem.

What is the balanced equation for ethane?

*asked on September 29, 2008* -
## math

the associative property allows you to change the order of terms in an expression. true or false my guess is True

*asked on February 2, 2015* -
## Chemistry - PLEASE HELP!!!

A 5.0 g n2o (laughing gas) that is inside a 12 mL cylinder used used to fill up a 800 mL whipped cream container. Beforehand, the container had air in it at 760 torr atmosphere pressure at 25 degrees celsius. Then, we will add the n2o/air mix to balloon

*asked on January 15, 2015* -
## earth science

During the summer _________ in India, wet air from the Indian ocean brings heavy rain to India.

*asked on December 30, 2014* -
## SCIENCE

The burning of fossil fuels cause the earth to get warmer by putting carbon dioxide in the atmosphere and the carbon dioxide traps heat. MY GUESS: TRUE

*asked on December 22, 2014* -
## Geography

I have an essay that says.. "It has been said that Eastern Europe is a political region more than a physical region. Would you agree or disagree with this statement? You must provide a solid argument for your position." since it asks me for my opinion how

*asked on December 8, 2014* -
## math

two students are playing a math game . the object of the game is to make the least possible number by arranging the given digits inside absolute value bars on a card . in the first round , each player will use the digits 3,5,and7 to fill in the card. One

*asked on September 25, 2014* -
## Finance

A company has identified the following investments as looking promising. Each requires an initial investment of $1.2 million. Which is the best investment? a)a perpetuity that generates a cash flow at the end of year 1 of $100,000, has a growth rate of

*asked on May 4, 2013* -
## Biology

Eutrophication refers to 1. the concentration of a toxic substance in the tissues of organisms. 2. depletion of mineral resources as a result of leaching. 3. the warming of the earth’s surface. 4. the damage to the ozone layer that protects the earth

*asked on March 19, 2013* -
## essay writing

The first sentence of your introductory paragraph should do all of the following EXCEPT: A.Give the reader an idea of the subject matter. B.Include the title of the essay. C.Grab the reader's attention. D.Provide a thesis sentence. I chose D.

*asked on February 3, 2011* -
## PRE CALC! HELP

1. a plane has heading of 54 degrees & airspeed of 225mph. The wind is blowing at 33mph from 144 degrees. what are its actua heading & airspeed? Round to one decimal place. A) 61.4deg, 257.1mph B) 7.4deg, 66114.0mph C) 136.6deg, 288mph D) no solution 2.

*asked on March 28, 2011* -
## math

i am a number in the fourth row on the hundred chart. my ones digit is twice my tens digit. what number am i;

*asked on September 19, 2010* -
## Math Prime Numbers

Grade 7 question: I am a two-digit prime number I am one less than a multiple of 10 If you add 30 to me you get another prime number Who am I _________?

*asked on September 8, 2008* -
## Calculus

I am having a lot of trouble doing these types of problems. Can someone show me how to do this. Thank you for your time. Evaluate the definite integral 4 x(x+3)dx 0

*asked on May 14, 2008* -
## Math adding fractions

What is the best way to add fractions and reduced them to the lowest terms example 3/8+1/3+5/6

*asked on November 30, 2007* -
## Chem

How were each of the following cations utimately separated from the rest of the group and /or decorated? The use of equations may be helpful, where applicable. Ag+ K+ Nh4+ Al+

*asked on November 15, 2015* -
## Statistics

Suppose we would like to estimate the mean amount of money spent on books by students in the fall semester. We have the following data from 400 randomly selected students: mean=$205 and s=$40. Assume that the amount spent on books by students is normally

*asked on February 27, 2015* -
## math

are the following a function 1. y=x/2 my guess is yes 2. y=2x+1 my guess is yes 3.y=x^2 my guess is yes 4.y=mx+b im not sure

*asked on February 3, 2015* -
## math

Is y=3x^2-2 a function? my guess is NO

*asked on February 2, 2015* -
## Math

if x-7=14 what is the value of x-2 Can someone help me with this. I know the answer, I just want to know how something like this is solved.

*asked on January 8, 2015* -
## earth science

the Julian calendar is the calendar we currently use. True or false. my guess is true

*asked on January 1, 2015* -
## Math

Hector has $450 and saves 20 per week. Tim has $1200and spends $30 per week.write a system equation for this situation

*asked on April 29, 2014* -
## English

We are working on Passive and Active voice. i really don't understand it, so do you know any websites that could help me with passive and active voice.

*asked on December 10, 2012* -
## Science

Why are space telescopes able to make better observations in the ultraviolet and infrared ranges than ground-based telescopes? A)space telescopes are closer to the objects that they are observing B) the atmosphere absorbs or reflects much of the UV and IR

*asked on April 15, 2012* -
## Earth/Space Science

Earth's axis tilts at an angle of 23.5 degrees relative to its orbit. Analyze the climate conditions that would exist at the poles and the equator if the axis were parallel to the orbit.

*asked on April 15, 2012* -
## Earth/Space Science

Cloud seeding, which causes rain by introducing condensation into a cloud, has been used to bring precipitation to areas experiencing drought. Analyze the benefits and risks of cloud seeding.

*asked on April 4, 2012* -
## Calculus

find the derivative: d/dx int_a to x (a being the upper limit) of tan(tan(t))dt

*asked on April 22, 2011* -
## Physics-please help

You're given a ramp 0.5m in height with a 3m incline. A mass of 1kg is at the top of the ramp and there is a friction of 2N. If the ramp has a force of friction of 2N, what will the speed at the bottom of the ramp be?

*asked on November 23, 2010* -
## math-plz help

Consider the curve f(x)=x^4 between x = -1 and x = 4. a)What is the volume obtained by revolving the area under the curve around the x-axis? b)What is the volume obtained by revolving the area under the curve (i.e. between f(x) and the x-axis) around the

*asked on February 2, 2010* -
## science

it has been hypothesized that chloroplasts originated from photosynthetic cyanobacteria that became symbiotic inside a host cell. Which of the following observations provides the strongest evidence for this suggestion? A) microscopically, chloroplast

*asked on May 11, 2015* -
## math

classify the following number as rational or irrational: 4.1 My guess is Rational

*asked on February 2, 2015* -
## math

Which relationship would most likely have a positive correlation? The amount of memory in computer, and the number of keys on the keyboard. The rate at which a train travels, and the time it takes for it to reach its destination. The number of tickets sold

*asked on February 2, 2015* -
## earth science

one reason the moon might be a better place than earth to study the universe is there is almost no atmosphere. True or False MY guess is false

*asked on January 1, 2015* -
## earth science

air pollution in pennsylvania causes ______ in new england because the wind blows the pollution into new England. can someone please help, I cant find this anywhere.

*asked on December 30, 2014* -
## Earth science

TRUE OR FALSE The burning of fossil fuels cause the earth to get warmer by putting carbon dioxide in the atmosphere and the carbon dioxide traps heat. MY GUESS: TRUE Isobars help meteorologists find fronts on weather maps. MY GUESS: FALSE A CLOUD IS A

*asked on December 22, 2014* -
## engineering

Hello guys.I got a homework and seem like I am stocked. a)What type of experiments should be done to find the relationship between the strength of concrete and water/cement ratio. b)what will be the range of the water/cement ratio? It would be great if you

*asked on May 4, 2014* -
## Physics. LAST PROBLEM!!

A small metal ball with a mass of m = 82.5 g is attached to a string of length l = 1.72 m. It is held at an angle of θ = 58.5° with respect to the vertical. The ball is then released. When the rope is vertical, the ball collides head-on and perfectly

*asked on March 26, 2013* -
## English

we are learning about the 14 tenses: past,present,future,past perfect,present perfect, future perfect, past progressive..., past perfect progressive..., emphatic..and then there is another one but i forgot what that one was. Anyway, i need a website that

*asked on December 10, 2012* -
## Math

Christine currently has $5000 in her 401(k) and plans to contribute $100 each month for the next 30 years into it. What will be the value of Christine's 402(k) in 30 years if the per annum rate of return is assumed to be 12% compounded monthly?

*asked on December 10, 2012* -
## Maths-Help needed!!!

Compare the graphs f(è)=sinè and f(è)=sin(-è). f(è)=cosè and f(è)=cos(-è). What conclusions can you make?

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

When was the telephone, atomic bomb, paper, flint tools, and the wheel invented? I've answered the other 4 and I think the telephone was invented in 1876. Please help.

*asked on April 21, 2012* -
## business

13. (TCO 2) Creating competition between employees within the corporation: (Points : 1) can encourage employees to deceive customers should focus on improving corporate profit must be ignored when corporate ethics are developed can bring out the best in

*asked on March 15, 2012* -
## Math

Solve for x and y X=1/6y Y=x-5

*asked on January 8, 2012* -
## Algebra

The illumination provided by a car’s headlight varies inversely as the square of the distance from the headlight. If a headlight produces 15 footcandles at a distance of 20 feet, what will be the illumination at 40 feet? At 100 feet?

*asked on October 22, 2011* -
## Calculus

Find the following interval: (2e^(2sqrt(y))/sqrt(y))

*asked on April 28, 2011* -
## essay writing

Which of the following will help you produce clear and effective writing? A. Brainstorming before writing. B. A rubric that provides criteria. C. The style of your paper. D. A solid thesis statement. I chose D.

*asked on February 3, 2011* -
## social studies

what do people speak in ukrain?

*asked on March 3, 2010* -
## Trigonometry- ??????

If vector a= (10,10) and vector b= (4,5) then ||a+b|| ≠ ||a|| + ||b||. Explain. I don't understand what this question is exactly asking, and I'm not sure how to answer it. Please explain. Thank you very much!!!

*asked on December 18, 2015* -
## Chem

How were each of the following cations utimately separated from the rest of the group and /or decorated? The use of equations may be helpful, where applicable. Ag+ K+ Nh4+ Al+

*asked on November 14, 2015* -
## Statistics

A criminologist is studying school violence, she selects a random sample of 25 adolescents aged 12 to 15 from a local middle school and asks the following,"How many times within the past school year have you been physically assaulted at school? She

*asked on February 27, 2015* -
## math

An equation is not a function if even one x value produces ____ corresponding y value(s). one less than one more than one zero for a my guess is more

*asked on February 3, 2015* -
## Physics

the charge on a pith ball was measured as +40 nC. if the charge on an electron is -1.6 x 10^-19, how many electrons have been added or removed from the ball?

*asked on January 31, 2015* -
## EARTH SCIENCE

Smog is the worst in.. A. Chicago B. New York C. Los Angles MY GUESS: C. LOS ANGLES

*asked on December 22, 2014* -
## english

writers portray the personalities of characters A. only through revealing the characters private thoughts. B. through plot complication. C. only if the plot is not important to the story. D. through a variety of methods.

*asked on May 28, 2014* -
## English

These are questions from Stephen King's collection "different seasons", particularly the novel "Rita Hayworth and the shawshank redemption": 1. From all the appearances the trial against Andy was pretty much "opens & shut". Identify the details that

*asked on May 28, 2013* -
## Ecology

The eﬀect of humans on the environment is more drastic than that of other species because people have a greater ability to 1. adapt to seasonal changes. 2. learn new skills. 3. alter the environment. 4. eat diﬀerent types of food.

*asked on March 19, 2013* -
## Chemistry

0.25mol of CO are mixed with 0.90mol of H2 and heated to 950 degrees celcius in a 15L flask at equilibrium 0.190mol of H2O were present, what is the concentration of the other reactants and products at equilibrium and what is Kc

*asked on March 16, 2013* -
## math

Write the expression thrice the sum of m and 8

*asked on November 27, 2012* -
## math

____ inches or 12 yards is the width of a tennis court

*asked on October 8, 2012* -
## pre calculus II

describe the domain, range,asymptotes and if the graph increase or decrease, and is this is a funtion from this equation y=5-3^x

*asked on September 18, 2012* -
## Math..plzz help

Compare the graphs f(¦È)=sin¨¨ and f(¦È)=sin(-¦È). f(¦È)=cos¨¨ and f(¦È)=cos(-¦È). What conclusions can you make?

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

You have 40.00 g of ice at -20.0C. You want ot convert all the ice to steam at 140.0 C. How much energy will it take to do so?

*asked on February 6, 2012* -
## math

Prove these identites I really need help with these I don't understand how to do them !!!! sin^2+tan^2=sec^2-cos^2 sin^2 sec^2 +sin^2=tan^2+sin^2

*asked on November 17, 2011* -
## math

Prove these identites I really need help with these I don't understand how to do them !!!! sin^2+tan^2=sec^2-cos^2 sin^2 sec^2 +sin^2=tan^2+sin^2

*asked on November 17, 2011* -
## geometry

Indicate in standard form the equation of the line passing through the given points. A(4, 1), B(5, 2) please help me

*asked on May 3, 2011*

## Pages

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