# Devin

Popular questions and responses by Devin-
## Conditional Probability

A certain virus infects one in every 400 people. A test used to detect the virus in a person is positive 90% of the time if the person has the virus and 10% of the time if the person does not have the virus. Let A be the event "the person is infected" and

*asked on December 15, 2016* -
## Calculus

In a 21 meter race between a turtle and a hare, the turtle leaves 8 minutes before the hare. The hare, by running at an average speed of 0.5 meters per hour faster than the turtle, crosses the finish line 4 minutes before the turtle. What are the average

*asked on November 14, 2017* -
## pre-cal

to find the distance AB across a river, a distance BC= 309m is laid off on one side of the river. It is found that B= 105.4 degrees and C= 12.2 degrees. Find AB To find the distance AB across a river, a distance BC= 309m is laid off on one side of the

*asked on June 5, 2007* -
## Chemistry

What is the percentage yield for a reaction if you predict the formation of 21 grams of C6H12 and actually recomvered only 3.8 grams? is the answer 18% 3.8g/21g x 100% pls verify.

*asked on October 17, 2010* -
## College Algebra

The logistic growth function f(t)= 100,000/5000e^-t describes the number of people, f(t), who have become ill with influenza t weeks after its initial outbreak in a particular community. A) How many people became ill with the flu after the epidemic began?

*asked on April 5, 2016* -
## Physics

A baseball is hit at ground level. The ball reaches its maximum height above ground level 3.2 s after being hit. Then 2.7 s after reaching its maximum height, the ball barely clears a fence that is 81.0 m from where it was hit. Assume the ground is level.

*asked on October 9, 2012* -
## social studies

Describe the governments in Mexico and Central America. i think mexico form of government is a democratic form of government, can somebody please just tell me what form of government central america has. ms.sue can you help me

*asked on November 16, 2018* -
## Enlish III

The graduation cermoney lasted only two hours. What part of the sentence is lasted only two hours? A) verb B) compound verb C) complete Predicate D) Complete subject

*asked on May 29, 2012* -
## physics

A 70 kg painter is painting the wall of a building. He stands on a horizontal board of length 4.7 m and mass 15 kg, suspended from vertical ropes attached to each end. If the painter stands 2.0 m from one end of the board, what would the tensions in the

*asked on December 11, 2010* -
## physics

estimate the rotational kinetic energy of earth, assuming it to be a solid sphere of uniform density

*asked on November 28, 2009* -
## math

Find the perimeter of the given triangle. Round your answer to the nearest tenth if necessary. ∆ADF, if ∆ADF ∼ ∆BCE, given BC = 17, BE = 9, CE = 12, and DF = 15. ∆BCE is inside of ∆ADF

*asked on December 9, 2017* -
## College Finite

Assume that the student has a cup with 13 writing implements: 7 pencils, 4 ball point pens, and 2 felt-tip pens. In how many ways can the selection be made if no more than one ball point pen is selected?

*asked on September 6, 2012* -
## AP Chemistry

What is the structure for PCl3Br2 and 3 isomers?

*asked on November 19, 2010* -
## algebra

A tree casts a shadow 10 ft long. A boy standing next to the tree casts a shadow 2.5 ft long. The triangle shown for the tree and its shadow is similar to the triangle shown for the boy and his shadow. If the boy is 5 ft tall, how tall is the tree?

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

Find x the angle of depression from the top of a lighthouse that is 181 ft above water level to the waterline of a ship 867 ft offshore. Round your answer to the nearest tenth of a degre

*asked on December 12, 2019* -
## Pre-Calculus

how do i find the vertical asymptote of x−1 / x(x-2) so far i got x-1 / x^2-2x

*asked on September 20, 2015* -
## math

Which algebraic expression represents “the difference of 54 and a number”?

*asked on September 8, 2015* -
## Chemistry

A 0.885 M solution of sulfuric acid (H2SO4) is to be reacted with a 0.552 M solution of sodium hydroxide to make sodium sulfate and water. How many L of the H2SO4 solution will react with 0.842 L of the NaOH solution? Give your answer to 3 decimal places.

*asked on April 29, 2015* -
## Chemistry

When a chemist burns ammonia according to the reaction below she finds that the reaction releases heat. (It is exothermic.) 4NH3(g) + 3O2(g) 2N2(g) + 6H2O(g) The enthalpy of the reaction DH = -1267 kJ. What is the enthalpy change (in kJ) when 7 grams of

*asked on January 12, 2015* -
## Physics

(a) How high a hill can a car coast up (engine disengaged) if friction is negligible and its initial speed is 96.0 km/h? (b) If, in actuality, a 750 kg car with an initial speed of 96.0 km/h is observed to coast up a hill to a height 18.0 m above its

*asked on October 17, 2014* -
## 8th grade math

At 2pm the temperature is 22 degrees, by 4am it is negative 7 degrees. We think the answer in the change of temperature is 29 degrees am I right?

*asked on September 30, 2014* -
## 8th grade Math

At 2pm the temperature is 22 degrees, by 4am it is negative 7 degrees. We think the answer in the change of temperature is 22 degrees am I right?

*asked on September 30, 2014* -
## Calculus

Graph the following function. Find and state the domain, intercepts, asymptotes, intervals of increase and decrease, local extrema, concavity, and inflections points. F(x)=(x+1)/(square root(x^2+1)) I got so far... Domain: (-infinity, infinity) Intercepts:

*asked on October 20, 2012* -
## Physics

A batter hits a pitched ball when the center of the ball is 1.35 m above the ground.The ball leaves the bat at an angle of 45° with the ground. With that launch, the ball should have a horizontal range (returning to the launch level) of 106 m. (a) Does

*asked on October 9, 2012* -
## chemistry

What is the density of a substance that weighs 500g and fills a container that is 1/2 liter in size?

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

Please show me the steps to solve this problem: The total shipping weight of two crates is 358 pounds. One crate weighs 124 pounds more than the other. What does eah crate weigh?

*asked on October 12, 2011* -
## Chemistry

How many milliliters of pure acetic acid (density = 1.05 g/mL) would be required to prepare 1.00 L of the solution?

*asked on November 16, 2010* -
## algebra

1. Imagine you are in the market for a new home and are interested in a new housing community under construction in a different city. a. The sales representative informs you that there are 56 houses for sale with two floor plans still available. Use x to

*asked on March 31, 2010* -
## Algebra 2

I need help-exam tomorrow! Although it is too late for your exam, in the future, we need specifics to provide help plus time to respond. We are volunteers and are not available 24/7. I hope this helps you in submitting future questions. Thanks for asking.

*asked on May 22, 2007* -
## Nursing

I need help i am working on a crossword puzzle and need help. I cant find the answers. 1. Excessive fluid in the tissue its 11 words. 2. The heart weakens blood enters the lungs its 22 words. 3. Skin cells die due to lack of blood flow its 14 words. 4.

*asked on March 22, 2020* -
## Math

Perry made $34,885 this year if the inflation rate was 6.5% how much was his salary actually worth

*asked on February 3, 2020* -
## Math

Nancy had an I come of $26,500 this year if the inflation rate was 11% what was her purchasing power

*asked on February 3, 2020* -
## Science

A horticulturist wants a plant that produces flowers with a certain size, color and fragrance but is not aware of any one plant having all of these traits. The quickest way she could achieve her goal would be to apply the process of

*asked on February 22, 2019* -
## math

Tell whether x and y are in a proportional relationship. If so, find the unit rate. Let y be the temperature x hours after midnight. The temperature is 60∘F at midnight and decreases 2∘F every 12 hour.

*asked on October 10, 2018* -
## math

9x-11 3x+43 ____________ L M N the value of x is

*asked on August 15, 2018* -
## math

for math test ncca/ equations and inequal

*asked on February 26, 2018* -
## Algebra

Jessie needs to rent a truck for two days to move her belongings to college. She can rent a U- Haul for $35 a day plus 25 cents per mile or she can rent a Budget Rental Truck for $25 per day plus 32 cents per mile. Write an equation and solve to find out

*asked on September 16, 2017* -
## Gaussian Elimination Method

Write the system of equations as an augmented matrix. Then solve for x and y. -3x-y=11 -9x-2y=34 Solution =

*asked on December 15, 2016* -
## Homework

A poll was taken of 10,439 working adults aged 40-70 to determine their level of education. The participants were classified by sex and by level of education. The results are shown below. Education Level Male Female Total High School or Less 2023 3264 5287

*asked on December 15, 2016* -
## Math Antics

A certain disease has an incidence rate of 0.5%. If the false negative rate is 7% and the false positive rate is 2%, compute the probability that a person who tests positive actually has the disease.

*asked on December 14, 2016* -
## Math

A football is kicked into the air. Its height in meters after t seconds is given by h(t)=-4.9 (t-2.4)^2+29. A. What was the height of the football when it was kicked? B. What is the maximum height of the kick? C. How long did it take for the football to

*asked on September 28, 2016* -
## Math

Bank A pays 4.79% compounded monthly, while Bank B pays 4.8% compounded quarterly. Which bank pays more?

*asked on March 5, 2016* -
## Math

County fair tickets can be ordered in advance. There is a one time processing fee of $10 per order. Individual tickets cost $3 a piece for rides and food. Write an algebraic expression to represent the total cost for a visit to the fair.

*asked on January 3, 2016* -
## ELA

What effect does Father’s return have on the Sakane family? A Yuki finds it hard to adjust to having both parents tell her what to do B Yuki’s mother continues to worry about the safety of her family C Ken is relieved that his father will take over as

*asked on December 5, 2015* -
## Chemistry

What is the order of the reaction for the following reaction and for each reagent given? A + 2B + C --> productions Experiment / A / B / C / rate 1 / 0.002 / 0.15 / 0.132 / 0.0057 2 / 0.002 / 0.25 / 0.132 / 0.0158 3 / 0.003 / 0.15 / 0.132 / 0.0114 4 /

*asked on September 13, 2015* -
## math

You get one spin.what is the probability of spinning a number larger than 6 out of 8.

*asked on August 19, 2015* -
## math

Kim has fraction 1 over 2 cup of almonds. She uses fraction 1 over 8 cup of almonds to make a batch of pancakes

*asked on July 6, 2015* -
## Chemistry

66.9 g of a substance X dissolves in enough water to make 0.428 L of a 0.68 M solution. Calculate the molar mass of X in g/mol.

*asked on April 29, 2015* -
## Economics

what is a hype song to rap to a economics question. Like this example: search (I'm on econ) on youtube

*asked on April 21, 2015* -
## math

Ty needs to cut strips of wrapping paper that are each 9 inches wide.If Ty has 2 rolls of wrapping paper that are 15 feet long, how many 9-inch strips can he cut ?

*asked on March 25, 2015* -
## physics

43. A block of mass 2.00 kg rests on a ramp tilted at 25.0°. Coefficients of friction for the block/ramp: μs = 0.300, μk = 0.100. A string passing over a high quality pulley connects the block with a bucket as shown below. The bucket contains sand but a

*asked on February 17, 2015* -
## Science

ranging minerals from the hardest to the softest. Chalk, fingernail. steel screw and paper clip

*asked on February 12, 2015* -
## Chemistry

Calculate the total heat (in Joules) needed to convert 1.602 x 101 grams of ice at -1.383oC to liquid water at 8.554 x 101oC. Melting point at 1 atm 0.0oC Cwater(s) = 2.09 J/goC Cwater(l) = 4.18 J/goC delta Hofus = 6.02 kJ/mol

*asked on January 12, 2015* -
## physics

A plane cruising along at 268 m/s, in straight level flight wants to drops a bomb. He is at a height of 1000m. At what distance should the pilot release the bomb in order to hit his target?

*asked on November 9, 2014* -
## Algebra

6-(-5r)=5r-3

*asked on September 19, 2014* -
## math

what is the exponential form of 1000 * 1000

*asked on August 25, 2014* -
## Algebra

Can anyone please show me how 3^n/6^(2n+1) becomes 1/2^n(6^(n+1))= 1/6)/12^n when you divide top and bottom by 3^n? Thank you and have a great day!

*asked on July 30, 2014* -
## statistics

To find out what people think, the Gallup Poll selected a random sample of 520 women and 506 men. The pollsters showed them a list of personal attributes and asked them to indicate whether each attribute was “generally more true of men or of women”.

*asked on June 27, 2014* -
## College Chemistry

1 L of N_2_ gas, having a pressure of 2.5 atm, is added 1 L of Ar gas, having a pressure of 3.7 atm, in a sealed, rigid flask. What is the final pressure in the flask?

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

How do you solve sqrt(1-(9/x^2))? I know the answer is sqrt x^2 -9/x but I'm not sure how to get the answer on my own. If you could show steps on how to get the answer that would help me a lot!

*asked on February 11, 2014* -
## math

how do I figure the circumference of race track that takes 3 lap to make a mile?

*asked on December 17, 2013* -
## math

Jeff Iron $250 on his $5000 certificate of deposit last year. what simple interest rate did the bank pay him?

*asked on July 14, 2013* -
## chemistry

A 7.56-g sample of gas is in a balloon that has a volume of 10.5 L. Under an external pressure of 1.05 atm, the balloon expands to a volume of 15.00 L. Then the gas is heated from 0.00 degree C to 25 C. If the specific heat of the gas is 0.909 J/g*C, what

*asked on July 13, 2013* -
## Complex Physics Problem

A ladder can fall for two reasons. If it is set too steep and climber gets their mass to the left of the ladder's base, the ladder likely will fall over backwards. If the ladder is set at too shallow of an angle the required force of friction between the

*asked on June 29, 2013* -
## College Level Physics

A horse pulls a cart with a force of 145 newtons at an angle of 30 degrees above the horizontal and moves along at a speed of 2.5 m/s. How much work to the nearest kJ does the force do in 6 minutes?

*asked on June 9, 2013* -
## Physics 1 College Level

A planet/moon has a mass of 77.89 × 1023 kg and a radius of 7.9 × 106 meters. What is g on the surface to the nearest hundredth of a m/s2? Once again, not really sure where to go with this. Out of the 10 problems I've only had trouble with this and one

*asked on June 1, 2013* -
## Physics 1 College Level

If D = 3204 meters and d = 1247 meters in the figure, what is the magnitude of the force on the space ship to the nearest MN? Consider all three to be point masses. I'm not even sure to begin with this question. Any help will be much appreciated!

*asked on June 1, 2013* -
## Math

A state lottery requires you to choose 4 cards from an ordinary deck: I heart, 1 club, 1 diamond, and 1 spade in that order from the 13 cards in each suit. If all four choices are selected by the lottery, yo win $5,000. It costs $1 to play. Find the

*asked on April 2, 2013* -
## probability

6 male students and 3 female students sit around a round table. What is the probability that no 2 female students sit beside each other?

*asked on March 25, 2013* -
## MATH

110% OF $8.50

*asked on March 15, 2013* -
## Calculus

The area bounded by the curve y = 2x^2-x^3 and line y=0 is rotated around the y-axis. The volume of the resulting structure can be expressed as V = a(pi)/b, where a and b are coprime positive integers. What is the value of a + b?

*asked on March 15, 2013* -
## Math

The velocity of a body A is given by v(t) = 2t^i + t 3^j. The body starts from rest at time t = 0 and position s(0) = 2^i 10^j. At what time, t, does the body cross the X axis? What is the average velocity of the body for the time interval, t = 0 and the

*asked on January 22, 2013* -
## Dynamics

The acceleration of a particle moving along a straight line is inversely proportional to its speed with the constant of porpotionality being k. The body starts from the position s = x0 ^i with initial speed v0. Determine the velocity of the particle as a

*asked on January 22, 2013* -
## Algebra2

Find and simplify a) f(a), b) f(a + h) and c) F(a+h) - f(a) / h ; 1. f(x) = x^2 + 5x -10

*asked on November 29, 2012* -
## Calculus

Can I simplify (x^.75)((200-3x)^.5)?

*asked on November 13, 2012* -
## Physics

A bullet with a mass m=12.5 g and speed v=85.4 m/s is fired into a wooden block with M=113 g which is initially at rest on a horizontal surface. The bullet is embedded into the block. The block-bullet combination slides across the surface for a distance d

*asked on October 25, 2012* -
## Successive approximations

Find all root of ln(4-x^2)=x correct to 8 decimal places. List all successive approximations.

*asked on October 20, 2012* -
## Physics

A baseball is hit at ground level. The ball reaches its maximum height above ground level 3.2 s after being hit. Then 2.7 s after reaching its maximum height, the ball barely clears a fence that is 81.0 m from where it was hit. Assume the ground is level.

*asked on October 9, 2012* -
## Physics

A train at a constant 44.0 km/h moves east for 42 min, then in a direction 45.0° east of due north for 17.0 min, and then west for 51.0 min. What are the (a) magnitude (in km/h) and (b) angle (relative to north, with east of north positive and west of

*asked on October 9, 2012* -
## Physics

A baseball is hit at ground level. The ball reaches its maximum height above ground level 3.2 s after being hit. Then 2.7 s after reaching its maximum height, the ball barely clears a fence that is 81.0 m from where it was hit. Assume the ground is level.

*asked on October 9, 2012* -
## practical english

Which of the following sentences contains an italicized word that's used as a predicate adjective? A. Jerry looks ILL today. B. Jerry looks INTO the microscope. C. Jerry looks disdainfully at the pile of laundry D. Jerry looks at the map. Is it c?

*asked on September 25, 2012* -
## Physics

How do I find Vector Resolution F = 0.300 g N, theta = 60 degrees. Do I take tan inverse (.3 sin 60/.3 cos 60)?

*asked on September 17, 2012* -
## college algebra

an executive invests $29,000 some at 7% and some at 6% annual interest. if he receives an annual return of $1870, how much is invested at each rate?

*asked on August 26, 2012* -
## College Physics

A person jumps from a window 34 meters high and is caught in a firefighter's net which stretches 0.6 meter. To the nearest m/s^2, what is the magnitude of the person's acceleration in the net?

*asked on August 26, 2012* -
## Geometry

Company "A" sells soil at 11 cents per cubic foot. While company "B" sells it at 3 dollars per cubic yard. You need to have 20 cubic yards of soil planted. What is the better company to go with? and how much will you save?

*asked on July 10, 2012* -
## chemistry

A gas has a volume of 50.0 cm3 at a temperature of -73°C. What volume would the gas occupy at a temperature of -123°C if the pressure stays constant?

*asked on April 23, 2012* -
## Calculus

a.) Given that f(3)=5 and f'(x)=x/((x^3)+3), find the linear approximation of f(x) at x=3. b.)If the linear approximation is used to estimate the value of f(2.9), will it be an overestimation or underestimation? Show justification

*asked on March 16, 2012* -
## Math

a.) Given that f(3)=5 and f'(x)=x/((x^3)+3), find the linear approximation of f(x) at x=3. b.)If the linear approximation is used to estimate the value of f(2.9), will it be an overestimation or underestimation? Show justification.

*asked on March 16, 2012* -
## Math

The stopping distance d of a car in feet is related to the speed in mph by the equation d(s)=.02s^2+1.1s Calculate the speed when your stopping distance is: 1.) 51ft 2.) 315.12ft

*asked on February 25, 2012* -
## Math

A math teacher wrote x^2+bx+c=0 on the board and asked students to find the two real roots. Alice miscopied one of the coefficients and found that 1 and 4 were the roots. Andy miscopied a different coefficient and found that -2 and 3 were the roots.

*asked on February 25, 2012* -
## science

need a example of the ecosystem cliche

*asked on January 11, 2012* -
## chemistry

Lewis dot of free radical cf2cl and hoco

*asked on December 5, 2011* -
## chemistry

Lewis dot of free radical cf2cl and hoco

*asked on December 5, 2011* -
## chemistry

The average out door concentration of carbon monoxide ,co at 15 c and 1 atm of pressure is about 900 micrograms per cm^3 . What is this concentration expressed : on ppm scale ? And on the molecules /cm^3scale?

*asked on December 5, 2011* -
## chemistry

If the radiicativr decay of nuclear explosion contains 90 Sr , with a half life of 28.1 years how long will it take for 99 of this radioaioot to decay

*asked on December 5, 2011* -
## chemistry

How many grams of na cl are required to make 500ml of a 0.65 percent w/v

*asked on December 5, 2011* -
## Algebra1

A CELL PHONE ORDDERS 500 NEW PHONES FROM A MANFACTURE.IF THE PROBABLITY OF A PHONE BEING DEFECTIVE IS 2.6% PREDICT HOW MANY OF THE PHONES ARE LIKELY TO BE DEFECTIVE.ROUND TO THE NEAREST WHOLE NUMBER

*asked on December 5, 2011* -
## Engineering

A 2kg piece of gold metal at 90 C is placed in 5 liters (=5kg) of water at 30 C. Determine the final temperature (Tf).

*asked on November 16, 2011* -
## Math

Find the roots of the given equation by completing the square: ax^2+bx+c=0

*asked on February 25, 2012* -
## algebra

The time it takes you to go 12 miles upstream is 5/4 the time it takes you to go 14 miles downstream. If the current is 3mph, how fast do you go in still water.

*asked on February 25, 2012*

## Pages

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