# Erin

Popular questions and responses by Erin-
## statistics

the probability that a football game will go into overtime is 17%. In 240 randomly selected football games, what is the mean and the standard deviation of the number that went into overtime

*asked on June 23, 2013* -
## physics

The outstretched hands and arms of a figure skater preparing for a spin can be considered a slender rod pivoting about an axis through its center. When the skater's hands and arms are brought in and wrapped around his body to execute the spin, the hands

*asked on April 12, 2008* -
## Physics

A man of mass 75 kg lies on a bed of 10,000 nails. The tip of each nail has an area of 1.0 square millimeter. What pressure does the man experience? [g=10 N/kg]

*asked on April 12, 2014* -
## calculus

Find the dimensions of the rectangle with area 225 square inches that has a minimum perimeter, and then find the minimum perimeter.

*asked on March 29, 2020* -
## Chemistry: help please

What is the millimolar solubility of oxygen gas,O2, in water at 20 degree celsius, if the pressure of oxygen is 1.00atm?

*asked on February 1, 2009* -
## Math

The Coffee Counter charges $11.00 per pound for Kenyan French Roast coffee and $15.00 per pound for Sumatran coffee. How much of each type should be used to make aa 24 pound blend that sells for $13.00 per pound?

*asked on January 22, 2018* -
## Elementary Statistics

1) Construct a confidence interval of the population proportion at the given level of confidence. x=60,n=300, 99% confidence. The 99% confidence interval is (_,_) 2) A researcher wishes to estimate the proportion of adults who have high-speed internet

*asked on June 6, 2012* -
## physics

A motorcycle stunt rider must jump a 100m wide canyon given a 20° ramp positioned on either side. What minimum speed is required so the rider will clear the canyon?

*asked on October 17, 2010* -
## chemistry

How do you do the hybridization of CBr4?

*asked on March 5, 2012* -
## physics

As you hurry to catch your flight at the airport, you encounter a moving walkway that is 85m long and has a speed of 2.2 m/s relative to the ground. If it takes you 68s to cover 85m when walking on the ground, how long will it take you to cover the same

*asked on October 2, 2011* -
## Physics

A uniform bar length of 2.0m and weight 1000 N has its center of gravity at its center. The bar is pivoted 0.5m from the right, and supports a weight of 200N on the opposite end (left end). What is the weight needed at right end of the bar to balance the

*asked on April 11, 2014* -
## Social Studies

Hi Jiskha!! I have been researching the Civil war and wanted to know it you can add to this. No this is not my work it is essays and summary's i found on the computer, this is what I found: Summary of the Civil War: Fought 1861-1865, the American Civil War

*asked on November 10, 2010* -
## Animal Art

1. Which of the following statements regarding the use of pastels with other mediums is true? A. Pastels should never be used for accents in a watercolor painting. B. An artist can effectively add charcoal over a pastel rendering. C. Pastel tends to deaden

*asked on March 27, 2007* -
## math

A hot air balloon descends at a rate of 320 feet per minute for 3 minutes. Whats the balloons total change in altitude?

*asked on May 17, 2013* -
## chemistry

Calculate the amount of heat required to completely sublime 24.0 g of solid dry ice CO_2 at its sublimation temperature. The heat of sublimation for carbon dioxide is 32.3 kJ/mol.

*asked on September 7, 2008* -
## Trig

Two ships leave a harbor at the same time. One ship travels on a bearing S11 degrees W at 12 mph. The second ship travels on a bearing N75 degrees E at 9 mph. How far apart will the ships be after 3 hours?

*asked on June 29, 2018* -
## chemistry

a liter of a solution saturated at 25C with CaC2O4 is evaporated to dryness giving a 0.0061 gm residue of CaC2O4. Calculate the concentrations of the ions, and the molar solubility and the solubility product constant for this salt at 25C. Show the balanced

*asked on June 10, 2012* -
## Chemistry

A pediatrician prescribes the antibiotic amoxicillin to treat a child suffering from an ear infection. The prescribed dose is to be 72.1 mg of drug per kilogram patient body mass per day. The drug is to be administered twice each day in the form of a

*asked on September 19, 2017* -
## Algebra

You operate a gaming Web site, where users must pay a small fee to log on. When you charged $3 the demand was 520 log-ons per month. When you lowered the price to $2.50, the demand increased to 780 log-ons per month. (a) Construct a linear demand function

*asked on February 21, 2012* -
## Physics

Liz rushes down onto a subway platform to find her train already departing. She stops and watches the cars go by. Each car is 8.60 m long. The first moves past her in 1.75 s and the second in 1.17 s. Find the constant acceleration of the train. I know how

*asked on October 10, 2009* -
## Algebra 2(check pt 4)

1)Cramer's Rule is used to solve the system of equations:3m-5n=12,4m+7n=-5 Which determinant represents the numerator for n? answer=[12 -5] [-5 7] 2)Cramer's Rule is used to solve the system of equations:3x-y+2z=17,4x+2y-3z=10,and 2x+5y-9z=-6 Which

*asked on July 28, 2007* -
## Math(check)

1)Find the range of the relation [(-1,4)},(2,5),(3,5)}.Then determine whether the relation is a funtion. 4,5,5 is the range 4,5 is a function 2)Find f(-1),if f(x)= x^2-6x/x+2 (-1)^2-6(-1)/-1+2 1+6/-1+2 7/1 =7 3)Find f(a),if f(t)= 2t^2-t-2. 2(a)^2-a-2

*asked on July 26, 2007* -
## English

"I watched Hassan get raped," I said to no one. Baba stirred in his sleep. Kaka Homayoun grunted. A part of me was hoping someone would wake up and hear, so I wouldn't have to live with this lie anymore. But no one woke up and in the silence that followed,

*asked on December 2, 2012* -
## math

Suppose you put $2000 in a savings account at an APR of 8% compounded quarterly. Fill in the table below. (Calculate the interest and compound it each quarter rather than using the compound interest formula. Round your answers to the nearest cent.) Quarter

*asked on October 24, 2017* -
## English

Read the following passage "I don't know anything," he said, "except that I'm beginning to be sorry we bought that room for the children. If children are neurotic at all, a room like that -" "It's supposed to help them work off their neuroses in a

*asked on May 2, 2016* -
## Physics

The Lamborghini Murcielago can accelerate from 0 to 27.8 m/s (100 km/hr or 62.2 mi/hr) in a time of 3.40 seconds. How fast will the car be traveling (m/s) after 5.1 seconds.

*asked on February 22, 2014* -
## grammar English

I am writing about interviewing Deaf Persons for my ASL research paper. The first person is Christian DeGuzman. He is profoundly deaf since birth, and about 2 or 3 years old later they found out that he was deaf that’s why. Christian grew up in Bay Area,

*asked on April 6, 2013* -
## Languege arts

1. Which is the BEST summary of "LAFFF"? (1 point) Angela used a time machine to win a writing contest. Peter and Angela invented a time machine. Peter used a time machine to travel to the future. 2. The author describes Peter's Halloween costume in order

*asked on February 7, 2013* -
## physics

It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.20 GPa). As one goes deeper and deeper in the ocean, the pressure increases by 1.0*10^4 Pa for every meter below the surface. If a diver goes down 33.0 m (a bit

*asked on April 13, 2008* -
## Algebra 2

The formula A = 180(n-2)/n relates to the measure A of an interior angle of a regular polygon to the number of sides n. If an interior angle measures 120 degrees, find the number of sides A)5 B)6 C)8 D)10 I have NO clue on how to do this pls help. Make A

*asked on July 15, 2007* -
## Math

The graph shown represents the equation y=3x- 9 Which equation also represents the line drawn on the graph? I just need help on this, can someone please explain how to break this question down? Thank you!

*asked on February 4, 2020* -
## Chemistry

The reaction of 5.25 g of Carbon with excess O2 yields 10.2 g of CO2. What is the percent yield of this reaction?

*asked on February 20, 2019* -
## Calculus

For an object whose velocity in ft/sec is given by v(t)=2sin(t),what is its distance,in feet, travelled on the interval t=1 to t=5?

*asked on January 27, 2019* -
## Trig

The magnitude and direction of two forces acting on an object are 100 pounds, S79degreesE, and 60 pounds N68degreesE, respectively. Find the magnitude, to the nearest tenth of a pound, and the direction angle, to the nearest tenth of a degree, of the

*asked on July 1, 2018* -
## Chemistry

We will calculate the amount of acid to use in each titration. Assume that you are using 0.0512 M NaOH(aq). A good volume of NaOH(aq) to use per titration is 15 mL. From this molarity and volume, the moles of NaOH can be calculated. Since the unknown acid

*asked on February 8, 2017* -
## Math

Solve the system of equations. 2x - 4y = 3 -3x + 5y = 1

*asked on October 25, 2013* -
## Math

How do you set this up? Solve the system using substitution: A boat travels 18 miles downstream in 1.5 hrs. It then takes the boat 3 hrs. to travel upstream the same distance. Find the speed of the boat in still water and the speed of the current. Thanks

*asked on December 6, 2012* -
## physics

A 9.1 g ball is hit into a 98 g block of clay at rest on a level surface. After impact, the block slides 8.0 m before coming to rest. If the coefficient of friction is 0.60, determine the speed of the ball before impact.

*asked on June 22, 2012* -
## Stats

Running times for 400 meters is usually distributed for young men between 18 and 30 years of age with a mean of 93 seconds and a standard deviation of 16 seconds. What percent of runners with finish after 110 minutes?

*asked on April 17, 2019* -
## History

What impact did industrialization have on imperialism? a. Developing European nations needed to conquer foreign territory to compete with industrialized nations b. An increase in production lead to the need for new land to build factories in foreign

*asked on February 25, 2019* -
## Trig

a. Find the magnitude of the force required to keep a 3100-pound car from sliding down a hill inclined at 5.7° from the horizontal. b. Find the magnitude of the force of the car against the hill.

*asked on July 14, 2018* -
## Math

A corporation has 7 members on its board of directors. How many different ways can it elect a president, vice president,secretary, and treasurer?

*asked on July 29, 2013* -
## anatomy

Voluntary actions are controlled within the _________ of the frontal lobe

*asked on July 26, 2011* -
## Chemistry

An alpha particle (mass 6.6 x 10^-24 grams) emitted by radium travels at 3.4 x 10^7 plus or minus 0.1 x 10^7 mi/h. (a) What is its de Broglie wavelength (in meters)? (b) Whats uncertainty in its position? for part (a) I got 1.53 meters which said it was

*asked on March 5, 2010* -
## physics

A tetherball leans against the smooth, frictionless post to which it is attached.The string is attached to the ball such that a line along the string passes through the center of the ball. The string is 1.20m long and the ball has a radius of 0.120mwith

*asked on February 27, 2008* -
## algebra

simplify: square root of 5 + square root of 20 - square root of 27 + square root of 147. simplify: 6/4square root of 2 sqrt 5 + sqrt 20 - sqrt 27 + sqrt 147 = sqrt 5 + sqrt (4*5) - sqrt (3*9) + sqrt (49*3) = 3 sqrt 5 - 3 sqrt 3 + 7 sqrt 3 = 3 sqrt 5 + 4

*asked on August 3, 2007* -
## Physics

A skateboarder at a skate park rides along the path. If the speed of the skateboarder at point A is v=1.4 m/s what is her speed at point B? Point A = 2.7 m & Point B=1.0 m

*asked on June 30, 2019* -
## Physics

A child pedals a tricycle, giving the driving wheel an angular speed of w=.875 rev/s. If the radius of the wheel is r=0.260 m, what is the child's linear speed, v?

*asked on June 30, 2019* -
## Chemistry

How many grams of CaCl2 are needed to prepare 25.0 mL of .500 M solution? and What volume of 12.00 M HCL is needed to prepare 150.0 mL of .500 M HCL?

*asked on April 17, 2017* -
## Chemistry

Assuming that the unknown acid sample in question 1 had a mass of 0.177 g, what is the molar mass of the unknown acid?

*asked on February 8, 2017* -
## Math 160

The position function of an object moving along a straight line is given by s = f(t). The average velocity of the object over the time interval [a, b] is the average rate of change of f over [a, b]; its (instantaneous) velocity at t = a is the rate of

*asked on September 3, 2016* -
## physics

A net force of 5.34 N acting for 4.23 s on a mass initial at rest, causes it to travel 4.75 m in a straight line. What is the mass?

*asked on October 2, 2014* -
## Physics

An object of mass 50 g floats in a liquid of density 2.5 g/ml. When the object is placed in a liquid of density 2.0 g/ml, it sinks to the bottom of the container. What is the force that the object exerts on the bottom of the container? [g = 10m/s^2 =

*asked on April 12, 2014* -
## Physics! Please help! :)

A concave mirror with a radius of curvature of 0.61 m is illuminated by a candle located on the symmetry axis 2.61 m from the mirror. Where is the image of the candle? Answer in units of m

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

can you check my grammar and spelling? and does it look better? Erin Oldham Calvin Brown 20 March 2013 ASL 2 ASL 2 Research paper I am writing about interviewing three Deaf Persons for my ASL research paper. The first person I interviewed is Christian

*asked on May 18, 2013* -
## statistics

Consider a normal distribution with mean 20 and standard deviation 3. What is the probability a value selected at random from this distribution is greater than 20?

*asked on May 12, 2013* -
## chemistry

will fe3+ oxidize Sn2+ to Sn4+ in acidic solution?

*asked on June 18, 2012* -
## Chemistry

Ammonia reacts with oxygen at 120 C to form NO and H20 in a sealed 40-L container. When 34 g of ammonia reacts with 96 g of oxygen, what is the partial pressure of the NO? What is the total pressure?

*asked on May 20, 2012* -
## physical science

In raising a 5000-N piano with a pulley system, the movers note that, for every 2m of rope pulled down, the piano rises 0.3m. Ideally, show that the force required to lift the piano is 500-N.

*asked on February 28, 2012* -
## Physics

Relative to the ground, a car has a velocity of 14.8 m/s, directed due north. Relative to this car, a truck has a velocity of 24.0 m/s, directed 52.0° north of east. What is the magnitude of the truck's velocity relative to the ground?

*asked on January 26, 2012* -
## college math

write the decimal as a fraction or a mixed number. write your answer in simplest form. .3282 so far i got this, 3282/100,000 then simplified to 1641/50,000

*asked on September 9, 2011* -
## geometry honors

if the volume of the pyramid is 64 feet cubed and the height is 16 feet what is the area of the base measured in square inches?

*asked on February 9, 2011* -
## Physics

A 210 g air-track glider is attached to a spring. The glider is pushed in 12.0 cm against the spring, then released. A student with a stopwatch finds that 13 oscillations take 16.0 s. Find the spring constant k.

*asked on January 21, 2011* -
## Chemistry

How many grams of NO gas can be produced from 80.0mL of 4.00M HNO3 and excess Cu? 3Cu + 8HNO3---3Cu(NO3)2 + 4H20 + NO

*asked on November 14, 2010* -
## physics

According to one set of measurements, the tensile strength of hair is 196 MPa, which produces a maximum strain of 0.400 in the hair. The thickness of hair varies considerably, but let's use a diameter of 50.0 u(mu)m . What is the magnitude of the force

*asked on April 18, 2008* -
## physics

A woman with mass 50.0kg is standing on the rim of a large disk that is rotating at 0.500rev/s about an axis perpendicular to it through its center. The disk has a mass of 110kg and a radius of 4.00m.

*asked on April 12, 2008* -
## algebra 2

(a-y)+2y3,if a= 2 and y= -3 (2--3)2 + 2(-3)3 (5)2 + (-6)3 25 + -216 -191 either im wrong somewhere or my book doesnt have that answer my choices are -29,43,79,-53 I am assuming that by 2(-3)3 you mean 2(-3)3 you did not follow the order of operation which

*asked on July 25, 2007* -
## Physics

The command module orbited at an altitude of 110 km above the lunar surface. How much time did it take for the command module to complete one orbit?

*asked on July 20, 2019* -
## science

How are biology as a science and the environment related?

*asked on June 25, 2019* -
## Chemistry

Calculate the wavelengths: -A muon (a sub particle with the mass of 1.884 X 10^-25g) traveling at 320.0 m/s -an electron (me=9.10939 x 10^-28g) moving at 3.85 x 10^6 m/s -An 83.0kg athlete running a "4 minute mile" (i.e. 400min/mile)

*asked on March 31, 2019* -
## Chemistry

I was able to get the balanced molecular equation but I am having a hard time getting the net ionic and oxidation half- reaction. Below is what I got for the balanced molecular equation: Al (s) + 3AgNO3 (aq) --> Al (NO3)3 (aq) + 3 Ag (s)

*asked on March 8, 2019* -
## Chemistry

According to the rules of golf, a golf ball cannot weigh more than 45.97 grams, and it must be at least 4.267 cm in diameter. The volume of a sphere is (4/3)πr3, where r is the radius. What is the density of a 45.67 g golf ball with a diameter of 4.267

*asked on February 9, 2019* -
## American history

Which event led to congress declaring war against mexico? A. The siege of the Alamo B. The Whitman massacre C. The Thornton affair D. The bear flag revolt is it A?

*asked on January 8, 2019* -
## Math

Jill said that an angle is made of any to rays is she correct explain

*asked on February 27, 2018* -
## Math

In 2009, a diabetic express company charged $39.95 for a vial of type A insulin and $30.49 for a vial of type B insulin. If a total of $1446.64 was collected for 40 vials of insulin, how many vials of each type were sold?

*asked on January 21, 2018* -
## Chemistry please help!

Calculate (triangle)H for the following gas-phase reaction: 2 H-C (3dashes) C-H + 5 O=O --> 4 O=C=O = 2 H-O-H -Using bond energies

*asked on April 5, 2017* -
## Chem Help!!!

A 1.00 mL aliquot of solution A was diluted to 50.00 mL using 0.02 M Fe(III), forming solution B (reaction 2) By looking at this how many moles of sodium salicylate were in the 1.00 mL aliquot used to prepare solution B?

*asked on April 2, 2017* -
## Chemistry

The spectrophometer was used to measure the absorbance of each of a series of [FeSa]+ solutions. A standard curve was construnceted by plotting the absorbance vs. concentration (M). The slope and y-intercept were found to be 1496 M-1 and .003,

*asked on April 2, 2017* -
## Chemistry

Given the reaction: Fe2SiO4 (s) + 2 H2CO3 (aq) ---> 2 FeCO3 (s) + H4SiO4 (aq) how many grams of Fe2SiO4 (s) are required to completely react with 55.0 mL of .500 M H2CO3 (aq) ?

*asked on March 8, 2017* -
## Chemistry

Given the reaction: Fe2SiO4 (s) + 2 H2CO3 (aq) ----> 2FeCO3 (s) + H4SiO4 (aq). How many grams of Fe2SiO4 are required to completely react with 55.0 mL of .500 M H2CO3 (aq)?

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

The balanced equation for the synthesis of water is: 2H2 + O2 > 2H2O If I have 5.5 grams of water, at least how many grams of Oxygen gas was needed?

*asked on January 21, 2017* -
## pre calculus work

given f(x)= 5x+4/5x^2+4x and g(x) = 1/x a. determine the domains of f(x) and g(x) b. simplify f(x) and find any vertical asymptotes c. explain how the two functions differ I have absolutely no idea how to answer this question - can you please help me to

*asked on August 19, 2016* -
## HUMAN DEVELOPMENT

The Seattle longitudinal study of cognitive development discovered that, among older people,

*asked on April 14, 2016* -
## Physics

A pilot flies out of Cleveland and sets his compass due North. He maintains an airspeed of 250 km/hr. After 30 minutes he finds that the plane is 200 km north and 40 km west of the starting point. What is the velocity of the wind? I've made my triangle and

*asked on January 26, 2016* -
## Microeconomics

If the price elasticity of demand is 2, this means that a __________ increase in price causes a __________ decrease in quantity demanded. A. 15%; 100% B. 15%; 10% C. 20%; 40% D. 30%; 20% answer B 15%, 10%

*asked on April 19, 2015* -
## Math

Find the number of the sides of a regular polygon, if the measure of one of its exterior angle is between 28 and 32.

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

If the measure of an interior angle of a regular polygon is 165, find the sum of the measures of its interior angles

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

The sum of the measures of four of the angles of a heptagon is 520. Two of the remaining three angles are congruent. The other remaining angle is 3/2 the measure of one of the two congruent angles. Find the measures of the remaining angles.

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

1. Victor brought a brand new car for 750,000. IF the value of the car depreciates 20% per year, what will it be worth during the fourth year? 2. Given the terms a10 = 3/512 and a15 = 3/16384 of a geometric sequence, find the exact value of the first term

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

A train leaves LAX traveling 65 MPH and another train leaves NY traveling at 35 MPH…at what destination will they collide

*asked on May 21, 2014* -
## Physics

Which of the following is the equation of the circle with centre (-1.5, 0.5) and radius 3? A. 2x^2 + 6x + 2y^2 - 2y - 13 = 0 B. 2x^2 - 6x + 2y^2 + 2y - 13 = 0 C. 2x^2 - 6x + 2y^2 - 2y - 13 = 0 D. 2x^2 + 6x + 2y^2 - 2y - 23 = 0 E. @x^2 + 6x + 2y^2 - 2y -14

*asked on April 12, 2014* -
## Biology

***I read the textbook assignment and I have read all the information on the lesson, however I cannot find the answer to this question. Nor can I find anything written about it anywhere in the lesson. Please help a girl out.*** True or False? There are

*asked on December 19, 2013* -
## Chem

Please help I have no idea how to do this. There are three different dichloroethylenes (molecular formulaC2H2Cl2), which we can designate X, Y, and Z. Compound X has no dipole moment, but compound Z does. Compounds X and Z each combine with hydrogen to

*asked on November 12, 2013* -
## organic chemistry isomers

which of the following molecules has a conformational isomer? CHCH CH2CH2 CH3CH2CH2CH3 CH2CCCH2 I think its either 2 or 4 but leaning towards 4. I just need help being more confident in my answer.

*asked on April 26, 2013* -
## Honors Chemistry

what volume of solution does a 3.0 molar solution need to have in order to contain 1.8 moles of sodium sulfate?

*asked on April 3, 2013* -
## Math

Please help! 1. A taxi cost $2.25 for the first mile plus .15 for each additional tenth of a mile. For a 5.2 mile trip Eric paid $10 and told the driver to keep the change. How much was the drivers tip? 2. 2 trillion is how much more than seven hundred

*asked on April 1, 2013* -
## maath HELPPPP

a ball is thrown into the air at a speed of 96 feet/sec. The equation that expresses the height of the ball as a function of time is: h(t) = -16t2 + 96t + 5 How long does the ball stay in the air after it is thrown? (Round answer to the hundreths of a

*asked on February 14, 2013* -
## math

a ball is thrown into the air at a speed of 96 feet/sec. The equation that expresses the height of the ball as a function of time is: h(t) = -16t2 + 96t + 5 How long does the ball stay in the air after it is thrown? (Round answer to the hundreths of a

*asked on February 14, 2013* -
## math (precalc)

Point S is 4 km west of point R, and point T is 4 km southwest of S. Find the bearing and distance from R to T. (If possible, show diagrams too, please! Thanks in advance.)

*asked on December 13, 2012* -
## College Physics 1

A mass is oscillating on a spring with a period of 4.60s. At t=0s the mass has zero speed is at x=8.30cm. What is the value of t the first time after t=0s that the mass is at x=4.15 cm?

*asked on November 28, 2012*