# Sophia

Popular questions and responses by Sophia-
## Math

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

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

A portrait of George Washington is square and has an area of 169 square centimeters. How long is each side of the portrait?

*asked on September 14, 2013* -
## 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* -
## 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

The Olympic record for the marathon set in 2008 is 2 h, 6 m, 32 s. The marathon distance is 26 mi. What was the average speed of the record-setting runner in km/h?

*asked on September 6, 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* -
## 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 (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* -
## 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* -
## human biology

if a cell lacks ATP, which of the following processes would cease to operate immediately? diffusion Na+/K= pump facilitated diffusion osmosis or passive transport

*asked on March 18, 2007* -
## 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* -
## 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

A two-digit locker combination is made up of two non-zero digits. Digits in a combination are not repeated and range from 3 through 8. Event A = choosing an odd number for the first digit Event B = choosing an odd number for the second digit If a

*asked on October 8, 2019* -
## 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

A wallet contains 3 dimes, 6 pennies, and 6 nickels. Event A is defined as drawing a dime on the first draw, and event B is defined as drawing a dime on the second draw. If Jack draws two coins from the wallet, one after the other without replacement, what

*asked on October 8, 2019* -
## physics

Two racing boats set out from the same dock and speed away at the same constant speed of 120 km/h for half an hour (0.500 h), the blue boat headed 23.7° south of west, and the green boat headed 34.4° south of west. During this half-hour (a) how much

*asked on September 23, 2015* -
## Chemistry

Which phrase is an example of what electrostatic forces hold together? Ag atoms and localized electrons in silver Cs+ and Cl− in CsCl Ar atoms in argon gas oxygen and hydrogen atoms in H2O

*asked on November 6, 2019* -
## Math

Michelle is interested in knowing how often girls in her class at school use their cell phones to instant message their friends. Which of the following methods could Michelle use to conduct a simple random sample to answer her question? A. Give the survey

*asked on October 8, 2019* -
## Math: Conditional Probability

A two-digit locker combination is made up of nonzero digits and no digit is repeated in any combination. Event A = the first digit is 1 Event B = the second digit is even If a combination is picked at random with each possible locker combination being

*asked on October 7, 2019* -
## Math:Probability

A locker combination consists of two nonzero digits, and each combination consists of different digits. Event A is defined as choosing an odd number as the first digit, and event B is defined as choosing an odd number as the second digit. If a combination

*asked on October 7, 2019* -
## Math

A jar contains 5 orange marbles, 3 black marbles, and 6 brown marbles. Event A = drawing a brown marble on the first draw Event B = drawing an orange marble on the second draw If two marbles are drawn from the jar, one after the other and not replaced,

*asked on October 5, 2019* -
## 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* -
## 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

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* -
## 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* -
## Ap chemistry

Write the balanced net ionic equation for the following chemical reaction: A solution of sodium dichromate, Na2Cr2O7, is added to an acidic solution containing Fe2+ ions.

*asked on December 15, 2019* -
## Math

Carol wanted to know about how much time students in her school spent surfing the Internet. So she asked 15 of her friends to complete a survey that she had prepared. Will the results of Carol’s survey represent the population of students in her school

*asked on October 9, 2019* -
## Math

Mrs. Greenaway has decided to open a new preschool in her town. To decide whether she will have enough students to be successful, she hires a researcher to conduct a survey of the town’s population. Which of the following groups would make up the best

*asked on October 9, 2019* -
## Math

Tally Lake is 11.25 miles long. Mary starts at one end and kayaks toward the other end, paddling at a constant rate of 2.5 miles per hour. At the same time, Ann starts out from the opposite end and paddles toward Mary at a constant rate of 2 miles per

*asked on August 26, 2019* -
## Math: Probability

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

*asked on April 29, 2019* -
## Social Studies

Do you know any facts or websites for Helen Keller

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

An unfair coin with Pr[H] = 2/3 is flipped. If the flip results in a head, then a marble is selected from an urn containing 9 red, 1 white, and 1 blue marbles. If the flip results in a tail then a marble is selected from an urn containing 10 red and 3

*asked on March 2, 2015* -
## Psychology

Describe the chi-square goodness-of-fit test.

*asked on June 8, 2014* -
## Psychology

Can you give a real world example of when you would use a chi-square test of independence and a chi-square goodness of fit?

*asked on June 8, 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* -
## Precalculus

cotx-cos^(3)xcscx

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

Hi, The resistance of each resistor in a series-parallel circuit was given and we measured the current and voltage across each resistor. Now, I have to find the theoretical values for I1, I2, etc. and V1, V2, V3, etc., using Kirchhoff's law and the known

*asked on February 28, 2010* -
## 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* -
## 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* -
## Physical science

Atoms form ________ bonds. A. physical B. chemical** C. atom D. nuclear

*asked on March 31, 2020* -
## Physical science

How does temperature affect chemical reaction rates? A. Low temperature starts a reaction. B. High temperature stops a reaction. C. Low temperature causes a faster reaction. D. High temperature causes a faster reaction.**

*asked on March 26, 2020* -
## AP Chemistry

Write the balanced net ionic equation for the following chemical reaction: Basic solutions of sodium sulfite, NaSO3, and potassium permanganate, KMnO4, are mixed.

*asked on December 15, 2019* -
## AP Chemistry

Hydrogen gas is blown over hot iron (ii) oxide. a. Write the balanced reduction half reaction that occurs. b. Write the balanced oxidation half reaction that occurs. c. Write the balanced net ionic equation for this reaction.

*asked on December 15, 2019* -
## AP Chemistry

Write the balanced reduction half-reaction for the decomposition of hydrogen peroxide.

*asked on December 15, 2019* -
## AP Chemistry

Write the balanced net ionic equation for the following chemical reaction: Solutions of nitric acid, HNO3, and barium sulfite, BaSO3, are mixed.

*asked on December 15, 2019* -
## AP Chemistry

Write the balanced net ionic equation for the following chemical reaction: Concentrated hydrochloric acid, HCl, is poured into a solution of potassium dichromate, K2Cr2O7.

*asked on December 15, 2019* -
## Math

A bag contains 4 blue balls, 7 yellow balls and 4 white balls. Event A is defined as drawing a blue ball on the first draw and event B is defined as drawing a white ball on the second draw. If two balls are drawn from the bag, one after the other and not

*asked on October 7, 2019* -
## Math

What is the equation of the line that passes through the points (15, 9) and (-2, 9)? It doesn't give me options.

*asked on October 4, 2019* -
## Math

A tether ball is attached to the top of a 15-foot pole. Maddy holds the ball 3 feet off the ground and 4 feet from the pole. How long is the rope that the tether ball is attached to?

*asked on September 4, 2019* -
## Algebra

If f(×)= 3x^2/×-2, then find f(4)

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

In poetry what are regular and irregular lines?

*asked on April 26, 2018* -
## 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* -
## 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* -
## 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* -
## 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* -
## error analyze

Can you check grammar error in this text? What can you do to reduce global warming in Thailand? Nowadays, The problem global warming is main problem for everybody in the world. It is effect on change of weather that the world have temperature highest. In

*asked on April 18, 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

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

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

in the poem lineage what does they mean

*asked on March 2, 2014* -
## Precalc

rewrite sinxtanx/(cosx+1) as an expression that doesn't involve a fraction.

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

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

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

cscx/1-sinx

*asked on October 23, 2012* -
## comm215

I have to write a 300-400 words essay on the following questions: Why overcrowding of school are causing teacher's to lose their jobs? -how is teacher layoffs the result of overcrowding? Please help.

*asked on August 1, 2011* -
## 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* -
## algebra

3x^3-2x^2y-8xy^2

*asked on February 2, 2011* -
## 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 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* -
## 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* -
## human biology

which of these characterisitics apply to exocytosis? requirese energy, requires, carrier proteins, requires channel proteins and/or requires vesicles. Thanks. Since this is not my area of expertise, I searched Google under the key words "exocytosis" to get

*asked on March 18, 2007* -
## algebra

At the birth of a baby, a couple decides to make an initial investment of C at the rate of 7% compounded annually so that the amount will grow to $30,000 by her 10th birthday. What should their initial investment be? Round to the nearest dollars.

*asked on May 13, 2020* -
## Physical science

In an acidic solution A. concentration of OH– > concentration of H+. B. concentration of OH– < concentration of H+. C. concentration of OH– = concentration of H+. D. concentration of H+ < concentration of OH–.

*asked on April 2, 2020* -
## Physical science

The gases in air dissolve in water. What would be one way to reduce the amount of a gas dissolved in water? A. add more water B. reduce the air pressure C. increase the air pressure** D. stir the water

*asked on April 1, 2020* -
## Physical science

Which of the following is the best explanation of the scientific method? A. The scientific method is a set of rules that every student should follow in science.** B. The scientific method is quite different than the way people solve everyday problems. C.

*asked on March 27, 2020* -
## Physical science

How does the law of conservation of matter apply to chemical equations? A. The sum of the coefficients on each side of the equation must be the same. B. The sum of the atomic masses on both sides of the equation must be the same.** C. The sum of the atomic

*asked on March 23, 2020* -
## Physical science

A helium atom has two protons, two neutrons and two electrons. What is the charge of this atom? A. 0 B. +2 C. +4*** D. More information is needed.

*asked on March 17, 2020* -
## Math

Can you help me on this question 3.89+42.71+12.32

*asked on January 6, 2020* -
## English

what can dice symbolize

*asked on December 15, 2019* -
## World History

People determine what to produce, how to produce it, and how to distribute it. = Market economy?

*asked on November 18, 2019* -
## math

an algebraic expression for 49 more than the product of 116 and b

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

Which of the following is an example of choosing a random sample from a target population of 100 students of which 40 are boys and 60 are girls? A. Choosing every other person on an alphabetical list of names. B. Choosing every 10th person from the list C.

*asked on October 9, 2019* -
## Math

The campaign manager for one of the five candidates running for office in a city wants to conduct a survey to see how popular his candidate is among all voters in the city. He chooses the first name on a voter registration list at random and then goes

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

A 7th grade student wants to find our which subject is the most popular subject among the 120 students in her grade. She decides to use an alphabetical list of student names from which to choose her sample. Which of the following is an example of a sample

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

A two-digit locker combination has two non-zero digits and no digit is repeated in any combination Event A = the first digit is less than 3 Event B = the second digit is less than 3 If a combination is picked at random with each possible locker combination

*asked on October 8, 2019* -
## Math: Conditional Probability

A bag contains 5 blue marbles, 8 green marbles, 4 red marbles, and 3 yellow marbles. Event A = drawing a green marble on the first draw Event B = drawing a blue marble on the second draw If Jasmine draws two marbles from the bag, one after the other and

*asked on October 7, 2019* -
## Math: Conditional Probability

Each house number on a street has 2 non-zero digits that are different. What is the probability that the second digit is less than 3, given that the first digit is less than 3?

*asked on October 7, 2019* -
## Math: Conditional Probability

A jar contains 4 brown marbles and 9 yellow marbles. Event A = drawing a yellow marble on the first draw Event B = drawing a brown marble on the second draw If two marbles are drawn from the jar, one after the other without replacement, what is P(A and B)

*asked on October 7, 2019* -
## Math

4, 12, 16, 48, 64, 192,__? What is the next number in the series?

*asked on October 1, 2019* -
## Social studies

Why did the English build Fort King George in 1721? as a key trading center for its valuable furs.*** to prevent Spanish and French attacks. as a key entrance to the Northwest Passage. to stop the spread of disease from the west.

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

The community raised twice the amount of money needed to buy a piece of land for the playground, with a given area. Jon and his dad decided to multiply the length and the width of the planned playground by 2. If the cost of the land is proportional to the

*asked on September 5, 2019* -
## Math

Cameron is 14 years old. She and her aunt are playing math games. Her aunt says, “If you multiply the difference between our ages by 4, you get 100.” How old is Cameron’s aunt?

*asked on September 3, 2019* -
## Math

On Friday, Dale and Lindsay each spent $5.00 on trading cards, and they each bought one package of chewing gum. On Saturday, Lindsay and her three sisters each spent $2.00 on trading cards, and each girl bought one package of gum. Lindsay noticed that the

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

A math problem asks when two brothers will have saved the same amount of money. When Marta writes and solves the equation, her final step is 3 = 7. Assuming Marta has done everything correctly, how should she interpret this solution? A. The brothers

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

Candace leaves her house and starts jogging at a pace of 480 feet per minute. Five minutes later, her brother runs after her at a pace of 660 feet per minute. If both of them continue at these speeds, how long will it take her brother to catch up? Here is

*asked on August 29, 2019* -
## math

Seventy-five times an integer, minus 36, equals 21 times the square of the integer. Which equation could be used to solve for the unknown integer?

*asked on August 27, 2019*