# LEO

Popular questions and responses by LEO-
## Chemistry

What is the pressure (in atmospheres) of the gas inside the container connected to an open-end, mercury-filled manometer as shown in the picture? The atmospheric pressure is 0.95atm. l----l | (G) l | l - --- l Hg l Hg *18cm - - --- Hg Hg HgHgHgHg what

*asked on October 21, 2007* -
## Physic

1. Water at a pressure of 3.00 x 10 5th Pa flows through a horizontal pipe at a speed of 1.00 m/s. The pipe narrows to one-fourth its original diameter. What is the speed of the flow in the narrow section? Not sure was successfully posted

*asked on December 5, 2012* -
## Economics (Net Present Value

Approximately 14 million Americans are addicted to drugs and alcohol. The federal government estimates that these addicts cost the U.S. economy $300 billion in medical expenses and lost productivity. Despite the enormous potential market, many biotech

*asked on September 7, 2015* -
## chem

Question: The American Dental Association recommends that an adult female should consume 3.0mg of fluoride (F-) per day to prevent tooth decay. If the fluoride is consumed as sodium fluoride (45.24% F), what amount of sodium fluoride contains the

*asked on October 1, 2007* -
## Chemistry

How many kilograms of chlorine are in 30kg of each of the following chlorofluorocarbons (CFC's)? CF2Cl2 -in kg's; CFCl3 -in kg's; C2F3Cl3 -in kg's?

*asked on October 1, 2007* -
## Algebra

Bernie has $16000 invested, part at 3% and the remainder at 5%. If the yearly interest on each investment is the same, how much interest does he receive each year?

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

What is m - 7

*asked on November 7, 2018* -
## Math

A piece of string is 3 yards long. How many 1 1/4-yard long pieces can Julie cut from the string? A. 1 B. 2 C. 3 D. 4

*asked on November 2, 2016* -
## physics

Hello everyone, I need help with this question: A dart gun is fired while being held horizontally at a height of 1.00m above ground level and while it is at rest relative to the ground. The dart from the gun travels a horizontal distance of 5.00m. A

*asked on September 4, 2012* -
## chemistry

how many oxygen atoms are in 1.60g of quartz - SiO2? how do you figure out atoms to grams and visa versa? the weight of 1 SiO2=60.0848g/mol. please help

*asked on October 1, 2007* -
## Math

Suppose you deposit $1000 in an account paying 4% annual interest, compounded monthly. How much money will you have after 15 years?

*asked on July 29, 2018* -
## Latin (GA Connections Academy)

Can you please help me with these translations? I know this is just homework help and not "we're going to solve your problems" but I have been slaving over these problems for hours and yes I have cried. I have scoured every resource available, including

*asked on May 17, 2018* -
## Physics

Two horizontal forces F1 and F2 act on a 1.7 kg disk that slides over frictionless ice, on which an xy coordinate system is laid out. Force F1 is in the negative direction of the x axis and has a magnitude of 3.0 N. Force F2 has a magnitude of 9.0 N. What

*asked on March 6, 2012* -
## Math

You plan to construct a brick wall measuring 4.5 m in length, 1.2 m high, and 0.5 m in width. If a brick measures 20 cm x 9 cm x 5 cm, how many bricks will you need? Total volume (to the nearest tenth) = ________ cubic meters. The number of bricks

*asked on June 14, 2012* -
## physics

An electron is accelerated from rest to a velocity of 2.0x10^7 m/s. a) if the electron travelled 0.10m while it was being accelerated, what was its acceleration? b)How long did the electron take to attain its final velocity? Please correct me if I'm wrong

*asked on December 13, 2012* -
## MATH STEVE

A piece of string is 3 yards long. How many 1 1/4-yard long pieces can Julie cut from the string? A. 1 B. 2 C. 3 D. 4

*asked on November 2, 2016* -
## Chemistry

It is estimated that uranium is relatively common in the earth’s crust, occurring in amounts of 4 g/metric ton. A metric ton is 1000 kg. At this concentration, what mass of uranium is present in 1.0 mg of the earth’s crust?

*asked on February 15, 2010* -
## math

A car has a 12 volt battery. The engine has a resistance of 0.22 ohms. How many amps will be drawn from the battery when the key is turned?

*asked on June 17, 2012* -
## geometry

A rectangular solid has sides of 10 cm, 6.5 cm, and 8.3 cm. What is its volume and surface area?

*asked on May 27, 2011* -
## algebra 2

PLEASE HELP ME WITH THIS QUESTION I DONT WANT TO FAIL AND I FEEL AS IF IM WRONG! The average daily minimum temperature for Pablo’s hometown can be modeled by the function f(x)=15.3sin(πx6)+44.1 , where f(x) is the temperature in °F and x is the month.

*asked on January 19, 2018* -
## science

which of the following will make it harder in the future to develop sustainable methods for humans using resources? A. there will be fewer renewable resources B.more humans will populate the earth C.biodiversity naturally reduces over time D.more humans

*asked on December 9, 2013* -
## chemistry

8.00g of NaOH are dissolved in water to make 3.00 L of solution. What is the concentration of hydronium ions, , in this solution?

*asked on November 15, 2009* -
## English

I'm writing a news report about a rocket club sets new launch record. I need ideas on what to write about that heading

*asked on March 8, 2015* -
## Math

The Smiths have a pool that is 20 feet by 35 feet. A 5 foot wide deck completely surrounds the pool. The average depth of the pool = 6 feet. How much surface area is covered by the proposed pool deck?

*asked on June 14, 2012* -
## physics

If a force of 60 N is exerted on a 15 kg object, calculate the acceleration that the object undergoes. ________m/s(squared)

*asked on June 14, 2012* -
## Chemistry

For the reaction, calculate how many grams of the product form when 3.2 g of Mg completely reacts. Assume that there is more than enough of the other reactant. 2Mg(s)+O2(g)→2MgO(s)

*asked on July 17, 2016* -
## physics - relative motion

A ferryboat, whose speed in still water is 4.00m/s, must cross a river whose current is 3.00m/s. The river runs from west to east and is 128m wide. The boat is pointed north. a) If the boat does not compensate for the flow of the river water and allows

*asked on December 18, 2012* -
## algebra 2

Logs are stacked 7 rows high. The top row has 15 logs, the second row has 18 logs, and the third row has 21 logs. This pattern continues similarly. What is the total number of logs in the stack?

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

This is confusing: This proportion can be changed to (0.45)y = x, where x represents the person's weight in kilograms and y represents the person's weight in pounds. The recommended protein in grams is numerically equal to the person's weight in kilograms.

*asked on June 17, 2012* -
## math-Probablity

A packet of carrot seeds has a germination rate of 92%. In other words, the probability of any seed sprouting is 0.92. How many seedlings would you expect in a row of 50 seeds?

*asked on June 5, 2012* -
## Science

A student finds that it takes 0.20s for a ball to pass through phototogates placed 30 cm apart on a level ramp. The end of the ramp is 92 cm above the floor. Where should a coin be placed so tnat the ball strikes it directly on impact with the ground?

*asked on November 12, 2007* -
## math

it costs $12.50 to see a movie at a theater near jason's house. it only costs $1,95 to rent a dvd from an online service a dvd player costs $125 to the nearest whole number, how many movies must jason watch on dvd instead of at the theater before he

*asked on February 18, 2015* -
## english

6. Which one of the following fragments is a prepositional phrase? A. During the darkest night B. Going to Cleveland C. Listening to her heart D. Completed her assignment I'm stuck between A & B please help me?

*asked on May 15, 2013* -
## math

At the local bank, 60% of the employees have 2 or more children. There are 240 employees that have fewer than 2 children. How many employees does the bank have?

*asked on January 18, 2016* -
## math

You must cover a hole that is elliptical in shape. You measure the major and minor axes and find them to be 6 ft. and 4.5 ft. respectively. If you want a 6 inch overhang around the hole, how much covering will you need? (Round to the tenths place.)

*asked on June 17, 2012* -
## math plz check ;-; sorry

A triangle has sides of lengths 5 cm, 5 cm, and square root 47cm. Which of the following statements is true? A. The triangle is an obtuse triangle because (√47)^2>5^2+5^2 B. The triangle is an acute triangle because 5^2

*asked on May 31, 2016* -
## Data management

A security code consists of either five or six different letters. How many distinct security codes are possible ANS:173659200

*asked on April 11, 2016* -
## chem

Consider the reaction when aqueous solutions of sodium nitrate and ammonium sulfide are combined. net ionic equation?

*asked on March 6, 2018* -
## Science

Cystic fibrosis is a recessive genetic disorder caused by a mutation of the CTRF gene. The disease is characterized by excessive mucus production along the respiratory and digestive tracts in addition to other symptoms. Cystic fibrosis is a progressive

*asked on October 31, 2017* -
## Chemistry Homework

Backpackers often use canisters of white gas to fuel a cooking stove’s burner. If one canister contains 2.45dL of white gas, and the density of the gas is 0.720g/cm3, what is the mass of the fuel in kilograms? So

*asked on June 3, 2016* -
## Algebra 2

Given that f(x) = x² + 4x, evaluate f(-2).

*asked on February 25, 2015* -
## Physics

If it takes an object 68 seconds to make 16 rotations, what would be the period of rotation? T=16/68 Is this right?

*asked on February 29, 2016* -
## Physics

A car traveling at 58 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 63 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant) acts on the passenger's

*asked on March 6, 2012* -
## Science

in a cladogram, a branch point represents a(n)____________ and a branch that ens without leading to living species represents___________. a. common ancestor,;extinction b.mutation; punctuated equilibrium c.extinct species: common ancestor D.common

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

The temperature of an object is raised by 90ºC. This is equivalent to what increase in its absolute temperature?

*asked on April 4, 2013* -
## pre calculus

1.) If h(x)= (fog)(x) and h(x) = 3 over the square root of x+3 , find g(x) if f(x)= 3 over the square root of x+2. my answer is x+1. Am I right? 2.)If f(x)=3x,g(x)=x-3,and h(x)= the square root of x, find (fogox)(X). I really didn't get this will someone

*asked on April 6, 2013* -
## Math

Aricela is trying to estimate the distance between her house and the park. On a map with a scale of 0.5 in. = 2 miles, the distance between her house and the park is 2.75 in. Which proportion can Aricela use to determine the distance, d, between her house

*asked on March 27, 2018* -
## chemistry

(a) A solution of 2.000 g of the compound Y(CH6N2O5) dissolved in 40.00 g water has a freezing point of -2.38 degree C. What is the molar mass of the compound Y(CH6N2O5) ? what is the implication of this molar mass? (Given that the freezing point

*asked on November 17, 2019* -
## Physics

1. It takes 190 kJ of work to accelerate a car from 21.0 m/s to 29.0 m/s. What is the car's mass? 2. A 32-kg girl is bouncing on a trampoline. During a certain interval after she leaves the surface of the trampoline, her kinetic energy decreases to 205 J

*asked on March 15, 2011* -
## Math

If a pool holds 22,000 gallons, how long will it take to fill the pool at a rate of 400 gallons per minute, rounded off to the nearest minute? _______ minutes Thank you

*asked on June 14, 2012* -
## Chemistry

A closed container is filled with oxygen. The pressure in the container is 435kPa . What is the pressure in millimeters of mercury? (i know that 1atm=760mm Hg=101,325 Pa) How do I use this to solve for the question? so: 435kPa*101,325=44,076,375Pa, & O2 =

*asked on October 20, 2007* -
## open-ended formatting tags no longer an issue

If you forget to end your bold or italic tags, this is no longer an issue. All formatting tags are terminated at the end of each post. Tags currently allowed for anyone to use are b, i, u, sup and sub. example It is still good practice, however, to pair

*asked on October 24, 2006* -
## Calculus 1

I'm asked to find max and min of: L(t)=12+2.8sin((2pi/365)(t-80). I find the derivative as: L'(t)=(5.6*pi/365)*cos[(2pi/365)(t-80)] but I get lost afterwards.

*asked on July 8, 2013* -
## math plz check ;-;

A triangle has sides of lengths 5 cm, 5 cm, and square root 47cm. Which of the following statements is true? A. The triangle is an obtuse triangle because (√47)^2>5^2+5^2 B. The triangle is an acute triangle because 5^2

*asked on May 31, 2016* -
## subject areas now display relevant questions

All of the subject areas now display relevant questions from the forum. Here are some great examples: Spanish: http://www.jiskha.com/foreign_languages/spanish/ Algebra: http://www.jiskha.com/mathematics/algebra/ Biology:

*asked on January 22, 2008* -
## solid mensuration

A cylindrical tank with flat ends has a diameter of two meters and is 5meters long. It is filled with fuel to a depth of one and one-half meters. Find the volume of the fuel in the tank in liters. plsss help!!

*asked on May 13, 2011* -
## chemistry

Sulfuric acid dissolves aluminum metal according to the following reaction: 2Al(s) + 3H2SO4(aq) -> Al2(SO4)3(aq) + 3H2(g) Suppose you wanted to dissolve an aluminum block with a mass of 15.9g . A)What minimum mass of H2SO4 (in g) would you need?

*asked on October 20, 2007* -
## READING

Well this is for the I know why the Caged bird discuss what Maya Angelou means by the title of her autobiography A bird in a cage is not free, but a captive. Canaries, for example, sing; why do you suppose that is? Because she is trapped she can’t do

*asked on June 24, 2011* -
## Physics

A cat rides a merry-go-round turning with uniform circular motion. At time t1 = 1.80 s, the cat's velocity is (3.60 m/s)i + (2.00 m/s)j , measured on a horizontal xy coordinate system. At t2 = 5.70 s, its velocity is (-3.60 m/s)i + (-2.00)j . What are (a)

*asked on February 23, 2011* -
## Physics

A supersonic aircraft produces a shock wave that describes a 30° cone. What happens to the angle of the cone as the aircraft travels faster?

*asked on April 4, 2013* -
## Math

Hannah's teacher brought in a bucket containing 72 blocks. The blocks are red, yellow or blue. Hannah wants to figure out the number of blue blocks without emptying the bucket. Hannah chooses a block from the bucket records its color and then replaces it.

*asked on February 12, 2013* -
## physics

an object weighs 3 lb. at 10 earth radii from its center. What is the object's weight on the earth's surface?

*asked on June 17, 2012* -
## chemistry

For each of the following acid-base reactions, calculate the mass (in grams) of each acid necessary to completely react with and neutralize 3.60g of the base. 2HNO_3(aq) + Ca(OH)2(aq) -> 2H_2O(l) + Ca(NO_3)2(aq) H_2SO_4(aq) + 2KOH(aq) -> 2H_2O(l) +

*asked on October 20, 2007* -
## physics

When the Sun is directly overhead, a hawk dives towards the ground with a constant velocity of 5.1 m/s at 45° below the horizontal. Calculate the speed of its shadow on the level ground. m/s

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

Isopropyl alcohol, C3H8O, is used in rubbing alcohol mixture. Alcohol on the skin cools by evaporation. How much heat(in kJ) is absorbred by the alcohol of 2.25g EVAPORATED? THE HEAT VAPORIZATION OF Isopropyl alcohol is 42.1 kJ/MOL Compute the number of

*asked on June 11, 2007* -
## math

24. If two sides of a triangle measure 14 and 19, what is the inequality for the third side? plsss helppp

*asked on January 10, 2020* -
## Chemistry

Name the following compounds 1. CH3-CH=CH-CH2 l Cl 2. CH3-CH-C=(tripple bond)C-CH3 l CH3 3. Cl Cl l l CH = C-CH3 4. Complete the following reactions and name the products a. CH2-CH=CH3+Cl2>>>> b. CH3-C=C-CH3+Br2 >>> Please help!

*asked on December 5, 2012* -
## 5th grade math

what is the least common multiple The least common multiple is the lowest possible number that has both numbers for a factor. For instance, if you are asked to find the LCM for 4 and 8, the LCM would be 8 because it is divisible by both 4 and 8. If you

*asked on October 5, 2006* -
## math

using exactly four 4s and only addition, subtraction, multiplication, and division, write an expression that equals each of the numbers from 1 to 10. you do not have to use all the operations, and numbers such as 44 are permitted

*asked on July 7, 2012* -
## Physics...Equilibrium (physics of a clothesline)

A clothesline is attached to two fixed ends which are 10.0m apart. A pulley of mass 40.0kg hangs freely in the middle of the line. The sag at the centre is 0.20m. Find the tension in each half of the clothesline.

*asked on January 3, 2013* -
## Physics

A 2.0-ohm resistor is connected in series with a 20.0-V battery and a three-branch parallel network with branches whose resistances are 8.0 ohms each. Ignoring the battery's internal resistance, what is the current in the battery?

*asked on April 4, 2013* -
## Math

A plumber's assistant's rate of pay is $0.75 per cubic foot of earth moved. He moves 220 cubic feet of earth to dig a trench. He moves the same amount to fill the trench. What is his pay for this job? $___________ (These questions are all confusing)

*asked on June 14, 2012* -
## Math

If a mixture of 24 lb. of cement, 48 lb. of sand, and 63 lb. of gravel is needed to make 1 cubic foot of concrete, how many pounds of sand are needed to pour a pool deck of 156 cubic feet? _______pounds

*asked on June 14, 2012* -
## Careers

can I become a dentist or paramedic without physics and pure mathematics ?

*asked on November 27, 2019* -
## Algebra II

What multiplies to 4 and adds to -2? I'm trying to find the zeroes of the function f(x)=x^2-2x-8. I did the AC/B tree (1*-8/-2) and from there I can't figure it out.

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

can someone help me solve this question. im not sure how to start so even some guidance would be helpful. thanks! One mole of O2(g) undergoes the following change in state. O2(g, 299 K, 4.38 bar) ⟶ O2(g, 252 K, 6.79 bar) What is ΔS for the gas? Assume

*asked on February 2, 2020* -
## Business Mathematics

Jungle Jim owes three debts: $500 due in one year plus interest at 6% semi-annually, $2000 due in two years, $1000 due in three years plus interest at 5% compounded monthly. He wishes to discharge these debts by paying $500 now and two equal but unknown

*asked on June 24, 2013* -
## Linear Algebra

Help me find my error! a)Write down the equation of the plane passing through the point (1,5,7) and parallel to the lines. Line A: Line B: Point x = 3- 2t x = 2 - 2t y = 1 - 5t y = 3 - 2t z = 2 - t z = 1 + 4t Parametric equation of the plane = + t1 + t2

*asked on December 6, 2018* -
## Chemistry

Hello, I'm having some trouble getting started on this question: "Calculate the volume and mass required to make 0.1 M solutions of Propionic Acid (1.0 M) and Sodium Propanoate (96.06 g/mol)" I would normally not have trouble answering this question when

*asked on March 3, 2015* -
## english

4. In which one of the following sentences does the subject come after the verb? A. Brock traveled over miles of dirt roads. B. On the next street, you'll find the shoe shop. C. Whenever he's in town, Jeremy likes to go fishing. D. Where is my Elvis CD? I

*asked on May 15, 2013* -
## how to sketch a graph of..

Local minimum and local maximum imply that the function approaches negative and positive infinite at opposite sides of the graph. Local minimum (1,1) and local maximum (3,3) means the slope of the function is 0 at these points. Thank you so much. So 1)when

*asked on November 5, 2006* -
## physics

Hello everyone, I need help with this question: A bartender slides a glass of beer down a bar with an initial velocity of 2m/s. The coefficient of kinetic friction of the bar is 0.05 and the length of the bar is 3m and the height of the bar is 1m. The mas

*asked on September 4, 2012* -
## language

analogy flower : rose as book is to what

*asked on December 5, 2019* -
## English

11. In which one of the following sentences is the simple subject also the complete subject? A. Crocodiles, quiet as logs, lurked on the riverbank. B. Detectives Homer Fry and Janine Small looked high and low for clues. C. Large and small dinosaurs stalked

*asked on May 15, 2013* -
## College math

From a survey of 100 college students, a marketing research company found that 60 students owned iPhones, 30 owned cars, and 25 owned both cars and iPhones. (a) How many students owned either a car or an iPhone (but not both)?

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

Jupiter's gravitational field at the surface is approximately three times that of the earth. A person weighing 120 lb. on the earth's surface would weigh how much on Jupiter?

*asked on June 17, 2012* -
## Plant Biology

Hi Can anyone tell me why using the scientific name for plants is important in the context of their evolutionary relationship ... 1)Is it something to do with extinction, and 2)The beneficial and harm to humans plants from the same species may cause. 3)

*asked on April 15, 2008* -
## Chemistry

What is the pressure (in atmospheres) of the gas inside the container connected to an open-end, mercury-filled manometer as shown in the picture? The atmospheric pressure is 0.95atm. l----l | (G) l | l - --- l Hg l Hg *18cm - - --- Hg Hg HgHgHgHg what

*asked on October 20, 2007* -
## grammar - showed versus shown

Which is the following sentences is grammatically correct? "She had shown me so much about love." "She had showed me so much about love." Thanks, Leo (webmaster)

*asked on September 27, 2007* -
## Algebra

Simplify each of the following expressions into simplest terms. a) {[-X+Y+(-2)*(-2Y)*[X-Y]}/[(X-Y)^2+(X+Y)^2] b) (X^3+4X^2Y+4XY^2+2XY-6Y^2)/(X+2Y)

*asked on May 5, 2013* -
## inorganic chemistry

what is the product of reaction dehydrated K3(Al(C2O4)3) with KMnO4 in the present of KOH?

*asked on April 27, 2013* -
## time management

As I spend more and more time working, I spend less time with family and friends. However, my career and financial success are important to me. How do I balance the time I spend making money versus time I spend with people? What are some critical questions

*asked on August 23, 2007* -
## message board threads

As you may have noticed, an entire thread can now be viewed by accessing the original message. I think this is great for students, and this may enhance search engine rankings. If anyone has serious objections to this, please let me know. Thanks, Leo I

*asked on October 24, 2006* -
## Algebra

You invest $5,500 into a 4.5% one-year CD. Find the balance of the account after five years if it's compounded: a. Quarterly Equation:______________________ Balance: $_________________ b. Annually Equation:______________________ Balance: $_________________

*asked on July 30, 2018* -
## math

Moffett’s Candy Factory makes candy in the shape of cylinders. The net of a cylindrical piece of candy is shown below. two circle with diameter of 4cm each and a rectangle with a lenght of 1.5 cm wha is the total surface area of this piece of candy?

*asked on January 19, 2014* -
## Math

What SAT score do you need to be in the top 20% of the population?

*asked on February 19, 2011* -
## chemistry

any one know how i can solve this question? What are the values of q, w, ΔU, ΔH, ΔS, ΔSsurr, and ΔSuniv for the following constant pressure process for a system containing 0.956 moles of CH3OH ? CH3OH(g, 122.0 ºC, 1.00 atm) ⟶ CH3OH(l, 34.0 ºC,

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

if 12 people can paint 15 houses in 24 days, how many days would it take for 3 people to paint 5 houses?

*asked on October 12, 2019* -
## grammar help /;-;/ plz check

Which sentence contains an error in the use of end marks or commas? A.In the garden were rows, and rows of peas, beans, carrots and radishes. B.A wind, nervous colt was bucking and refusing to enter the trailer. C.The book, in my humble opinion, seemed a

*asked on May 23, 2016* -
## finance

In computing the cost of common equity, if D1 goes downward and Po goes up, Ke will

*asked on February 9, 2011*