# sophia

Most popular questions and responses by sophia-
## Math (Calculus Optimization)

An oil field contains 8 wells, which produce a total of 1600 barrels of oil per day. For each additional well that is drilled, the average production per well decreases by 10 barrels per day. How many additional wells should be drilled to obtain the

*asked on June 27, 2017* -
## Math 6

n ice cream stand sells chocolate, vanilla, and strawberry ice cream as well as a choice of 22 toppings. How many choices are there for a single flavor of ice cream with one topping? How do I do this? is it 46 choices? Am I right?

*asked on May 10, 2014* -
## Math

List out the elements of the set "The letters of the word Mississippi"

*asked on October 1, 2014* -
## Physics

About how much pressure do the feet of a 6000-kg elephant exert on the ground? Assume each foot has area of 0.10 square meters.

*asked on February 20, 2011* -
## Chemistry

1. A student collected the following data for a fixed volume of gas: Temperature (⁰C) Pressure (mm of Hg) 10 726 20 750 40 800 70 880 100 960 150 ??? Fill in the missing data point. Show all calculations leading to an answer.

*asked on December 28, 2016* -
## Organic Chemistry

If fructose, glucose, and sucrose are the only carbohydrates in honey, how could you use Benedict's reagent to determine the number of moles of sucrose in a 1.0g sample of honey?

*asked on March 8, 2011* -
## Chmistry

Write a balanced chemical equation for the combustion of acetylene if the products are: a) Carbon and water vapour b) Carbon monoxide and water vapour c) Carbon, carbon dioxide. Carbon monoxide and water vapour d) The complete combustion of acetylene

*asked on March 28, 2016* -
## Physics

The equation y=5 sin(3x-4), where y is in mm, x is in m and t is in secs, represents a wave motion. Determine the frequency, period and speed of the wave

*asked on February 26, 2018* -
## Biochemistry 105

8. Arrange the following molecules in the order of increasing polarity. a. (PH3, HCl, H2O, CCl4) b. (NH3, HF, H2O, HBr)

*asked on February 12, 2017* -
## Math

A textbook weighs 2.5 pounds.How many kilograms does the textbook weigh? Round your answer to the nearest tenth of a pound. 1kg =2.2 lb - - Helllpp

*asked on November 30, 2018* -
## Chemistry

“1.25 g of crushed limestone was added to 50.0 cm3 of 1.00 mol dm-3 hydrochloric acid (an excess). The mixture was left until all bubbling stopped and was then made up carefully to 250 cm3 with pure water. A 25.0 cm3 sample of this was pipetted into a

*asked on November 10, 2010* -
## Math

the population of new york city doubles during the workday. at the end of the workday, the population decreases by half. if the population in new york city is roughly 4,000,000 people before rush hour, and morning rush hour lasts 3 hours. what would be the

*asked on September 9, 2018* -
## physics

An airplane traveling 1001 m above the ocean at 125km/h is going to drop a box of supplies to shipwrecked victims below. What is the horizontal distance between the plane and the victims when the box is dropped?

*asked on January 25, 2009* -
## Math: Probability

A bag has 2 red marbles, 1 blue marble and 4 gold marbles. What is the probability of drawing two gold marbles, if the first marble is replaced after it is drawn? is it 16/49 or 7/13

*asked on April 28, 2019* -
## Statistics

A manufacturer makes two models of an item: model I, which accounts for 80% of unit sales, and model II, which accounts for 20% of unit sales. Because of defects, the manufacturer has to replace (or exchange) 10% of its model I and 18% of its model II. If

*asked on October 4, 2007* -
## Physics

What is the mass of the air in a room that has dimensions of 10m x 30m x 4m?

*asked on February 20, 2011* -
## Chemistry

Which of the following is true about oxidation reactions? A. Oxidation reactions are the principal source of energy on Earth. B. All oxidation reactions are accompanied by reduction reactions. C. The burning of wood in a fireplace and the metabolization of

*asked on December 28, 2016* -
## Chemistry

A plasma reaction converts A (Molecular weight = 200) to B and uses NAD as a co-substrate and produces NADH as a by product (1 mole of NADH is produced per every 1 mole of A converted to B). The amount of NADH can be determined by monitoring its’

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

Three softball teams ordered equipment from the same catalog. The first team spent $285 on 5 shirts, 4 caps, and 8 bats. The second team spent $210 on 12 shirts and 6 caps. The third team spent $250 for 7 shirts, 10 caps, and 3 bats. What were the catalog

*asked on January 30, 2017* -
## Algebra

Suppose you want to enclose a rectangular garden plot against a house using fencing on three sides, as shown at the left. Assume you have 50 ft. of fencing material and want to create a garden with an area of 150 ft². A. Let w = the width. Write an

*asked on December 1, 2015* -
## Algebra

A baker bakes a batch of muffins and splits the batch evenly onto six different trays. She then adds five croissants to each tray. If each tray now contains at least twenty baked goods, what is the least possible number of muffins in the baker's original

*asked on May 25, 2015* -
## Phyics

Bob heads out into a lake at an angle of 41◦ with respect to the shore. If his boat is capable of a speed of 1.7 m/s, how far from land will he be in 7 min and 17 s ? Answer in units of m.

*asked on October 15, 2016* -
## Precalculus

cotx-cos^(3)xcscx

*asked on October 22, 2012* -
## Chemistry

How much SO2 is needed to saturate 50g of H2O at 5 degrees Celsius

*asked on April 27, 2015* -
## Utah state history

1. The contributions of the mountain men include... A: developing first Anglo- American settlements B: establishing good relations with the Native Americans C: developing local resources D: establishing routes through the region for others to follow

*asked on February 14, 2018* -
## math

When an airplane experiences drag, are the forces added or subtracted? Hint: Drag is the term used to describe the air in front of the plane pushing the airplane backwards.

*asked on October 2, 2018* -
## Math

Leena bakes a loaf of bread. She eats 1/8 of the loaf and gives 1/6 of it to each of her 3 friends. What fraction of the loaf of bread is left?

*asked on February 8, 2015* -
## SCIENCE

PISTILS AND STAMENS REACH MATURITY AT DIFFERENT TIMES, WHY WOULD THIS BE AN ADVANTAGE TO THE PLANT?

*asked on April 1, 2008* -
## Information Technology

Develop an algorithm, flow chart and pseudocode that accept as input three unit test scores and a project score for seven students. The algorithm, flow chart and pseudocode should accept seven examination scores. The students's overall score comprised of

*asked on October 23, 2012* -
## Math: Probability

My locker combination has three digits. None of the digits are zero. What is the probability that the first digit of my locker combination is less than 4? A) 3/10 B) 1/3 C) 2/5 D) 4/9

*asked on April 28, 2019* -
## physics

A small dog is trained to jump straight up a distance of 1.2 m. How much kinetic energy does the 7.2-kg dog need to jump this high? (The acceleration due to gravity is 9.8 m/s2.) Show your work for credit.

*asked on February 5, 2017* -
## Math

A package of spaghetti weighs 266 grams. ow many ounces does the package weigh? 1 oz = 28 g

*asked on December 5, 2018* -
## Physics

Thank you Damon for answering my other question.. I appreciate... The distance between two successive crests of a water wave travelling at 3.6m/s is 0.45m. Calculate the frequency of the wave?

*asked on February 26, 2018* -
## Social Studies

Why is Texas referred to as the Lone Star state? I think it is because of the flag has one star I just dont know if that is right.

*asked on May 13, 2019* -
## Math: Probability

A bag has 2 red marbles, 1 blue marble and 4 gold marbles. What is the probability of drawing two gold marbles, if the first marble is replaced after it is drawn?

*asked on April 28, 2019* -
## Reading

What is a preposition? What is the preposition in this sentence? "Sally read her book in the living room."

*asked on April 26, 2018* -
## Math

A locker combination has three nonzero digits, and digits cannot be repeated. If the first digit is 3, what is the probability that the next digit is odd? A.4/9 B.1/5 C.1/2 D.5/9

*asked on April 28, 2019* -
## math

Carlita saw 5 times as many robins as cardinals while bird watching. She saw a total of 24 birds. How many more robins did she see than cardinals

*asked on November 7, 2016* -
## Math

Can anyone help me with 2(y+2)for Y=2

*asked on December 9, 2018* -
## Precalc

suppose you want to invest $60,000 for ten years. You can invest your money in a CD that earns 4% interest, compounded quarterly and has no risk, or you can invest your money in futures that ear 10% interest, compounded quarterly. However, the second

*asked on November 5, 2015* -
## Pre calc- confused

Geometry/Maximum area: A rancher wants to enlarge an existing rectangular corral such that the total area of the new corral is 1.5 times that of the original corral. The current corral's dimensions are 250 feet by 160 feet. The rancher wants to increase

*asked on October 15, 2015* -
## Chemistry

The solubility of CaCO3 at 25 degrees celsius is 6.90*10-5M. The reaction is CaCO3(s)-->Ca 2+(aq) + CO3 2-(aq)

*asked on February 13, 2008* -
## Math: Probability

Jake rolls two number cubes. What is the probability that both numbers are greater than 4?

*asked on April 29, 2019* -
## Math

The media center at Josh's school has a computer area. The first 4 rows have 6 computers each. The fifth row has 4 computers. How many computers are there?

*asked on October 27, 2018* -
## science

6. identify the action-reaction pairs of forces for the following situations: (a) you step off a curb. (b) you pat your tutor on the back (c) a wave hits a rocky shore.

*asked on February 3, 2011* -
## World History

List two ways the Atlantic Slave trade affected Africa.

*asked on July 26, 2009* -
## physics

A pitched ball is hit by a batter at a 45-degree angle and just clears the outfield fence, 98 m away. If the fence is at the same height as the pitch, find the velocity of the ball when it left the bat. Ignore air resistance.

*asked on January 25, 2009* -
## Math: Probability

A locker combination has three nonzero digits, and digits cannot be repeated. If the first two digits are even, what is the probability that the third digit is even?

*asked on April 29, 2019* -
## Math

A locker combination has three nonzero digits, and digits cannot be repeated. If the first two digits are even, what is the probability that the third digit is even? A) 7/9 B) 1/3 C) 1/6 D) 1/7

*asked on April 28, 2019* -
## Math

Find the distance from the point to a. the originb. the z-axis. I’d be very glad if you could help me

*asked on November 29, 2018* -
## Math

In math class, a student has an average grade of 85% for five tests so far. What grade must that student earn on the next test to reach an average grade of 90% for all six tests?

*asked on December 1, 2016* -
## World Regional Studies/ Geography

In January 2000, cyanide is released to the Tisza River in Hungary. Effect 1: Effect 2: Water Pollution Countries develop industries. Effect 1: Effect 2: Poland’s water in most rivers is unsafe to drink Rain washes fertilizers from fields into bodies of

*asked on October 16, 2014* -
## Math

Given A = (7, 1, 3), C = (4, -2, 3), B = (5, 1, 2), and D = (6, m, n), find m and n so that segments BD and AC have the same midpoint. Is ABCD a parallelogram? Explain. Please help! I’d be very thankful

*asked on November 29, 2018* -
## Physics

A person walks 21 m East and then walks 34 m at an angle 32◦ North of East. What is the magnitude of the total displacement? Answer in units of m.

*asked on October 15, 2016* -
## Math riddle PIZZAZZ Worksheet

What happened to the grocer who stacked all of the liquid detergent no the high shelf? plzzz help

*asked on October 30, 2008* -
## physics

A mass of 135 g of an element is known to contain 30.1 1023 atoms. What is the element? hydrogen oxyden aluminum carbon Is it aluminum?

*asked on April 26, 2008* -
## Maths

An amount of money is shared by three people in the ratio 2 : 5 : 8. What fraction of this money is given to the person who receives the smallest share?

*asked on August 17, 2016* -
## Physics! Case II

A woman at an airport is pulling her 25.0 kg by a strap at an angle of 25 ° above the horizontal as shown in figure Fig. P5.44. She pulls on the strap with a 45.0 N force, and friction is negligible. What is the acceleration of the suitcase? ___m/s^2

*asked on December 3, 2012* -
## Social Studies

Do you know any facts or websites for Helen Keller

*asked on April 24, 2019* -
## Math

How many solutiond in the interval of 0 < x < 360 should you expect for the equation asin(bx+c)+d=d+a/2 A does not equal to 0 and b is a positive integer. I have cancelled the d’s and i understand the range will be from a to a-, but i dont get how to get

*asked on April 14, 2019* -
## Math

If m∠CBD = 148°, what is m∠ABE

*asked on April 9, 2019* -
## Physics

What is the direction of this resultant vector (between the limits of −180◦ and +180◦ from the positive x-axis) ? 1. −88◦ 2. −117◦ 3. −144◦ 4. −143◦ 5. −135◦ 6. −171◦

*asked on October 15, 2016* -
## math

a set of five positive integers has a mean median and range of 7 how many distant sets whose members are listed from least to greatest could have these properties

*asked on July 2, 2014* -
## PHYSICS URGENT! PLEASE FRICTION CASE 2

A 13 kg box is at rest on a level floor. The coefficient of static friction µS = 0.9 and the coefficient of kinetic friction µK = 0.8. Audrey is applying a 140 N push at an angle (=20°) as shown in Figure 1. C) What is the magnitude of FNormal on box

*asked on December 4, 2012* -
## Math

here is the question: Freida must take a 4-hour exam containing 200 questions, 50 of which are math. Twice as much time should be allowed for each math ques as for each other type of question. What is the total # of minutes she should allow for the math

*asked on November 12, 2009* -
## Math

The median number of magazine appearances made by 7 models is 5. The range of number of magazine appearances by those models is 5. Determine if the following statement is true, is false, or does not contain enough information. At least one of the models

*asked on October 14, 2017* -
## MATH HELP PLEASE I HAVE NEVER BEEN MORE CONFUSED

The value of a car decreases at a constant rate. After 1 year the value of the car is $20,000. After 2 more yearsit is $14,000. Write an equation in slope-intercept that represents the value y (in dollars) of the car after x years.

*asked on October 22, 2016* -
## math

The value of a car decreases at a constant rate. After 1 year the value of the car is $20,000. After 2 more yearsit is $14,000. Write an equation in slope-intercept that represents the value y (in dollars) of the car after x years.

*asked on October 22, 2016* -
## English

My homework is about identifying independent and dependent clauses The sentence in () marks is the clause they're asking for. 1. The narrator's mother worked on her inventions at night, (after her husband fell asleep) - Dependent Clause 2. She would work

*asked on January 14, 2016* -
## Math: Probability

A bag has 2 red marbles, 1 blue marble and 4 gold marbles. What is the probability of drawing two gold marbles, if the first marble is replaced after it is drawn? C. 4/7 D. 7/13 ( I didn't add A or B `cause i knew those were wrong)

*asked on April 28, 2019* -
## Math

How do you explain the meaning of 0?

*asked on August 8, 2018* -
## math

24 How many 5-letter “words” can be formed from the letters of the word FORMULATED, if each must contain 2 vowels and 3 consonants? How many of these will have the vowels at the two ends on the “word”?

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

The value of a car decreases at a constant rate as it grows older. When the car is 2 years old, it is worth $23,000. When the car is 5 years old it is worth $15,500. Write and equation relating y (value of the car $) to x (age of car).

*asked on October 22, 2016* -
## Math

How can you use decimal squares to represent the product 0 * 0.7?

*asked on December 9, 2014* -
## Math

Find x so that the distance from (x,-4,2) to the origin is 6 units.

*asked on November 29, 2018* -
## math

maya and winston share some cookies in the ratio 2:3. maya had 3 fewer cookies than winston how many cookies they share altogether?

*asked on January 18, 2017* -
## Algebra 1 college

How much of a 12% saline solution should be mixed with a 4% saline solution to obtain 40 milliliters of a 6% saline solution?. Use a system of equations and elimination method to solve. can someone please see if I am on the right track. 12T + 4F=6x40 -4

*asked on February 3, 2016* -
## math

The value of a car decreases at a constant rate as it grows older. When the car is 2 years old, it is worth $23,000. When the car is 5 years old it is worth $15,500. Write and equation relating y (value of the car $) to x (age of car). Is it

*asked on November 7, 2009* -
## math

Find the number of ways in which 9 people can be divided into 2 groups: the first group has 5 people and the second group has 4 people.

*asked on April 15, 2018* -
## Math

1. the points given are two of the 3 vertices of a right triangle. Which could be the third vertex of the triangle given 2 points are (-4,-5) & (3,2) ? 2.) A circle with center O and radius r is intersected at 2 distinct points by line l. Which is true? a.

*asked on November 9, 2015* -
## Math

Alan scored a total of 14 points for answering all the 15 questions on a math quiz. For every correctly answered question, Alan got 2 points. For every wrong answer, he lost 2 points. How many questions did he answer correctly?

*asked on March 11, 2015* -
## Math

A cone with base diameter of 60m and height of 45m is given. For the volume calculation purposes of the cone, it is approximated via an inscribed regular decagonal pyramid (number of base edges is ten). Find the percent error of this volume

*asked on November 29, 2018* -
## Poetry

In poetry what are regular and irregular lines?

*asked on April 26, 2018* -
## Math

Dello, i need help with this problem. Find the periodic withdrawals PMT for the annuity given. HINT [See Example 4.] (Assume end-of-period withdrawals and compounding at the same intervals as withdrawals. Round your answer to the nearest cent.) $100,000 at

*asked on March 2, 2018* -
## Physics

A half pipe can be thought of as half of a cylinder with radius of 7.00m. If a skater with mass 75.0 kg, starts with an initial velocity of 5.00 m/s at the top of the ramp, (a), what is his velocity at the very bottom of the ramp? The skater then

*asked on March 23, 2017* -
## Math

Write a story problem that can be represented with 1152÷24

*asked on February 28, 2017* -
## Physics

A superhero flies 185 m from the top of a tall building at an angle of 15◦ below the horizontal. What is the horizontal component of the superhero’s displacement? Draw the vectors to scale on a graph to determine the answer. Answer in units of m. Your

*asked on October 16, 2016* -
## math ( subtracting fractions)

12 1/4- 4 1/8 When you add or subtract fractions, you have to have the same denominator. In this problem you have to change 1/4 to 2/8. Then subtract the fraction and then subtract the whole number. Please post your answer and we'll be glad to check it.

*asked on January 31, 2007* -
## maths

amelie is x years old her sister is four years older her brother is three times her age the sum of their age is 44 years

*asked on November 28, 2016* -
## Spanish

Can someone check my answers to this? I'm really confused on these practice problems. Thanks! Directions: Using informal, formal, plural and nosotros commands (use Dop's/Iop's if needed) to correctly answer the questions. The names in parathenisis are what

*asked on January 31, 2015* -
## math

The shortest side of an isosceles triangle is labeled, in inches, in the triangle below. The two longer sides are 6 inches longer than the shortest side. The perimeter of the triangle is 33 inches. Picture shows an isosceles triangle with 2x-3 under it

*asked on January 16, 2019* -
## math

In how many ways can a committee of 12 people, of which 5 must be in the 21−30 age group, 4 must be in the 31−40 age group and 3 must be in the 41−50 age group, be chosen if there are 6 people of each age group?

*asked on April 15, 2018* -
## Statistics

For a set of scores with a mean of 111 and a standard deviation of 8, what is the percentile rank of 90? (round to two decimal places, no leading zeros)

*asked on April 24, 2016* -
## Chemistry(MOLEDAY)

I created my Mole: MOLE'YMPICS *(Olympics)*... That is my Mole-word or Phrase but Idk if my descriptive caption below would be a phrase. I don't know what my descriptive caption could be. Or at least Idk how to make it FUNNY or HUMOROUS? My original

*asked on October 22, 2015* -
## Math

After 14 boys leave the concert, the ratio of boys to girls is 3 to 10. If there are p girls at the concert, write an algebraic expression for the number of boys at the beginning of the concert in terms of p

*asked on January 24, 2013* -
## Precalc

Rewrite cot(^2)xcosx/(cscx-1) as an expression that doesn't involve a fraction.

*asked on October 23, 2012* -
## Math

The 4ft by 6ft has a solid red rectangular area that covers 1/3 of the flag. What could be the dimensions of this red area?

*asked on March 8, 2012* -
## comm215

please help me correct my essay. the topic of the essay is:"Why overcrowding of school are causing teacher's to lose their jobs overcrowding? and how teacher layoffs are the result of overcrowding." below is a copy of the essay i wrote... One main concern

*asked on August 1, 2011* -
## 9th grade algebra

daniels print shop purchased a new printer for $35,000. Each year it depreciated at a rate of 5%. What will its approximate value be at the end of the fourth year?

*asked on May 4, 2010* -
## 5th grade

matt ran 1/5 mile less on monday than on tuesday. he ran 1/2 mile less on wednesday than he did on monday. he ran 7/10 mile more on friday than on wednesday. if matt ran 4/5 mile on friday, how far did he run on tuesday? stumped, please help!

*asked on November 6, 2009*