Saturday
April 30, 2016

# Posts by alex

Total # Posts: 3,415

Physics
An object is placed 20.0 cm to the left of a convex lens with a focal length of +8.0 cm. Where is the image of the object? A)28 cm to the right of the lens B)13 cm to the left of the lens C)13 cm to the right of the lens
May 21, 2015

help
The sum of two numbers is 20. One number is 3 times the other. Find the numbers.
May 20, 2015

math
The Bishop's Peak 4-H club is having its annual fundraising dinner. Adults pay \$35 apiece and children pay \$20 apiece. If the number of adult tickets sold is twice the number of children's tickets sold, and the total income for the dinner is \$1,890, how many of each ...
May 20, 2015

math
2 N 11D ?
May 20, 2015

math
Diane has \$1.20 in dimes and nickels. She has a total of 13 coins. How many of each kind does she have?
May 20, 2015

mathematicalmodel
This is very true, I haven't got the answer, but the exam finishes today. I am not interested in using it to pass, but I would like to see the working (if possible, when the exam is finished!)
May 19, 2015

mathematicalmodel
I can not figure this out! has anyone got it?
May 19, 2015

physics
Work=change in potential energy therefore W=mgh = 75kg*9.8m/s^2*1.75m = 1286.25 J
May 19, 2015

Calculus
The following definite integral gives the area of the region between the graph of the function f(x) = Icosx - x^2I (I=modulus), the x-asis, and the lines x=-2 and x=2. the integral of mod cosx - x^2 from -2 to 2. Describe a different region whose area is given by this integral...
May 19, 2015

Calculas
and this got me to Galagan's answer of 4*pi... but still not sure so don't take my answer for it Galagan.
May 19, 2015

Calculas
hhmmmm... i used the equation v=integral of pi*y^2 from a to b.
May 19, 2015

Math
Simplify -5x-5y+3+x+2y-3.
May 14, 2015

Computer science
Write the pseudocode for a method that receives as input the cost of a meal, and then adds a 9% tax rate, and then outputs a 15% tip on top of the price+tax
May 13, 2015

Science
When a water wave with a positive amplitude of one meter meets another water wave with a negative amplitude of one meter, what will be the result? Explain.
May 11, 2015

Science
What is the formula for the frequency of visible light? Using this formula, explain what will happen to the frequency when yellow light (580 nanometers) is slowed down slightly when it passes through a crystal.
May 11, 2015

life orientation
Alien & Sedition Acts.
May 11, 2015

Chemistry
A voltaic cell consists of an Mn/Mn2+ half-cell and a Pb/Pb2+ half-cell. Calculate [Pb2+] when [Mn2+] is 2.1 M and Ecell = 0.13 V.
May 4, 2015

history
What geographical advantage does the Italian landscape have over the Greek landscape?
April 29, 2015

history
How long did the Byzantine Empire last?
April 29, 2015

science
How much heat is added to 10 g of water when you start from room temperature and heat it to its boiling point?
April 27, 2015

That makes a lot more sense....
April 27, 2015

My reasoning behind changing my name was to see if alphabetic order mattered, but it doesn't..... just wanted to let you know....(=
April 27, 2015

1) Which of the following most directly made possible the Age of Exploration? A) hydropower B) caravel C) aqueduct D) wind turbine 2) Which region of Western Europe experiences an arctic climate. A) the Iberian Peninsula B) Italy and Greece C) the British Isles D) Northern ...
April 27, 2015

Chemistry
One mole of N2 and 3 moles of H2 are placed in a flask at 375 degree celsius.? Calculate the total pressure of the system at equilibrium if the mole fraction of NH3 is found to be 0.21. The Kp for the reaction is 4.21 x 10 raise to -4
April 22, 2015

Science
The effect _______ explains how fast air moves across a surface, the ____ pressure that presses on that surface. In contrast, the more ____ that air moves, the more of _____ there will be. I'm sorry that it might not make sense, I translated it from French. I tried using ...
April 21, 2015

Math
Hi again. Just realised that i got B wrong. So it means i need that too. Just to clarify (b) Show that if x and y are related by the equation √x + √y = 1 then dy _____ dx= 􀀀-√(y/x) _ _ I got -√y/-√x.
April 21, 2015

Math
In this problem we consider drawing some straight lines which form a nice pattern. Consider joining the point (0.1,0) to the point (0,0.9) by a line segment; then joining (0.2,0) to (0,0.8) by a line segment; and so on. In general, consider joining the points (a,0) and (0,b) ...
April 21, 2015

history
Gaul is the Roman term for what modern country?
April 20, 2015

Math
7. You are having a discussion about sequences with your classmate. She insists that the sequence 2, 3, 5, 8, 12 must be either arithmetic or geometric. Is she correct or incorrect? Explain.
April 17, 2015

AP Chemistry
The thing is I tried the negative p delta v on my UT homework, and it didn't accept so I thought maybe moles had something to do with it. Unless I was doing the equation wrong.
April 16, 2015

AP Chemistry
How much work is done by the system when 2.00 moles of O2 expand from a volume of 3.00 liters to a volume of 5.1 liters against a constant external pressure of 0.0100 atm? Answer in units of J. I get w=-p(deltaV) but what about moles?
April 16, 2015

Chris has made the following grades on five math test. 90,74,86,75,94 What score must Chris earn on the next math test to have a test average of exactly 85?
April 14, 2015

While battling a forest fire , Samuel was only able to get three hours of sleep during the first day. What was the percent of the day was Sam awake F. 87.5% G. 37.5% H. 90% J. 10%
April 14, 2015

As of july 2004, the population Was 293,027,571 if more than half of these peaple live within 80 kilometers of an ocean,about how many peaple live within that distance show your work
April 13, 2015

Physics
A spring of length 10.0 cm and spring constant 160 kN/m is compressed to a length of 4.00 cm. If, when released, it pushes a block of mass 100 kg, a) what is the speed of the block after it slides up a 15.0 cm hill? b) What is its speed after it falls into a 10.0 cm dip?
April 9, 2015

ttu
The triprotic acid H3A has ionization constants of Ka1 = 2.5× 10–4, Ka2 = 3.4× 10–8, and Ka3 = 5.4× 10–13. Calculate the following values for a 0.0760 M solution of NaH2A
April 9, 2015

chemistry
how many electrons can n=4 l=1 have?
April 8, 2015

Spanish
in that case if you are referring to a specific cafeteria like the school's cafeteria it would be "la comida de la cafeteria no es saludable" if not then "la comida de cafeteria no es saludable"
April 7, 2015

Spanish
Are you going to write it with in a sentence or by itself?
April 7, 2015

ela help me on this please damon,reed,writeacher
"inappropriate" lol'd
April 1, 2015

Trigonometry
Solve each equation, giving a general formula for all of the solutions: a. 2sin^2(x)-5 sin(x)-3=0 b. (cos(x)-((sqrt2)/2))(sec(x)-1)=0
March 28, 2015

Trigonometry
Solve each equation for theta, giving a general formula for all of the solutions: a. tan(theta)=-1 b. sin(theta/2)=1/2
March 28, 2015

English
i dont know
March 25, 2015

English
During our summer vacations, we would always go out to our cabin by Butterfly Creek. The trips were always fun and relaxing. We would take hikes, photograph the wildlife, and swim in the river. Wildflowers in high meadows. Butterflies hovering. I still remember the smell of ...
March 25, 2015

science
based on the masses of CaCl2 and Na3PO4 you determined from the periodic table, what mass combining ratio would you predict?
March 22, 2015

Chemistry
If there are 57.6 mL of water that change from 19.4 degrees Celsius to 34.7 degrees Celsius, calculate the number of joules of energy transferred in the form of heat. Round to the nearest whole number. The specific heat capacity of water is 4.18 J/g*C and density of water is 1...
March 22, 2015

Economics
1. What determines the size of the key-money payments that landlords demand (and tenants offer) for the right to rent a controlled apartment? 2. Who, other than the owners of rental units, loses as a result of rent controls? Who gains from rent controls? What effect would the ...
March 20, 2015

Stereo Inc. sells a stereo system for \$500 down and monthly payments of \$60 for the next 4 years. If the interest rate is 1.75% per month, find: a) The cost of the stereo. b) The total amount of interest paid.
March 18, 2015

French, foreign language
Read each definition and write the appropriate word or expression in the space provided. 1. C'est un plat typiquement français. On les prépare avec du beurre et de l'ail. Ce sont un escargot . (incorrect) 4.On les utilise pour faire des omelettes. Ce sont...
March 18, 2015

French, foreign language
Hi, I need help with answering some questions for French Here's my work on them tell me what you came up with for each question that is incorrect: 1.C'est un plat typiquement français. On les prépare avec du beurre et de l'ail. Ce sont un escargot (...
March 17, 2015

calculus
1.) Find the derivative of ((x + 3)/e^x) ^ (Log e X) 2.) T/F (log e X)' = (log e |x|)' 3.) T/F (Log e 7x)' = (log e x)' 4.) Find the derivative of e^(log e 7x)
March 15, 2015

algebra
March 13, 2015

The coordinates of two vertices of triangle DEF are D(-5,5) and E(9,8). Determine two possible coordinates for for F that would make DEF a right triangle ? ans: slope DE = 8-5 / 9 - (-3) = 3/12 I don't know this part :how to Determine two possible coordinates for for F ...
March 12, 2015

Physics
A pilot wants to fly directly north to an airport 500 km away. His speed relative to the air is 100 km/h. Howevere there is a 40 km/h cross wind blowing from west to east. At what angle relative to the south north direction should he fly to arrive at the distant airport? How ...
March 11, 2015

Foreign Language, French
Can you please proofread my answers to the questions assigned by my teacher and correct me where needed? 1. découvrir / vieille / qu'est-ce qu' / dans / ils / valise / la Qu'-est-ce qu' ils veieille ont découvert la valise? 2. cette / nous / ...
March 10, 2015

science
Part I: Units of Measurement for Gas Laws For the following questions, use the following answer choices to indicate what each unit of measurement is used to measure (pressure, volume, or temperature). 1. atm 2. kPa 3. L 4. oC 5. torr 6. K 7. mL 8. cubic centimeters (cm3) ...
March 2, 2015

chemistry
everything
March 2, 2015

chemistry
Find the molar masses of the following compounds: 1. LiI 2. PbCO4 3. Mg(OH)2 4. (NH4)3PO4 Find the percent composition (percent by mass) of the given element in the following compounds: 1. Fluorine in AgF 2. Hydrogen in glucose (C6H12O6) 3. Oxygen in Fe2(SO4)3 PART II: ...
March 2, 2015

Chemistry Help
Thank you so much DrBob222. Now I understand.
February 27, 2015

Chemistry Help
February 27, 2015

Chemistry Help
The theoretical yield of Cl2 that could be prepared by mixing 15.0 g of manganese dioxide (MnO2) with 30.0 g of HCl is 12.2 g. The limiting reagent was MnO2. When the reaction was run only 8.82 g of Cl2 was collected. The percent yield of Cl2 is_? a)58.8 % b)72.3 % c)29.4 % d)...
February 27, 2015

Calculus II
A square plate of side 3 m is submerged in water at an incline of 30 degrees with the horizontal. Calculate the fluid force on one side of the plate if the top of the plate lies at a depth of 6 m. (* The only thing i can think to use is the equation: p * g * (S from a to b of...
February 26, 2015

No, because the area of any triangle Is (height * width)/2. BTW I'm in fourth grade.
February 25, 2015

Math
Describe how to rename an improper fraction as a mixed number. Use an example to explain. I don't get the "renaming" part. Does it mean to explain how to convert it?
February 24, 2015

French
5 - Les vacances You are preparing a family vacation in Europe. Rewrite each sentence using two pronouns. Pay particular attention to the agreement of the past participle. 1.-L'agence de voyages a envoyé les billets d'avion à mes parents. 2.-Mes parents ...
February 24, 2015

French
Did I do this correctly: 1. Malika / une pêche Malika a demande une peche, mais il lui a donne une poire. 2. Soraya / une tomate Soraya a demande une tomate, mais il lui a donne un oignon. 3. Daniel / du pâté Daniel a demande du pate, mais il lui a donne des...
February 24, 2015

math
Is this right 6(5y-4) 30y-24 Need help with this one -3+2(6z-3+4)
February 24, 2015

Math
You roll a number cube and get a one 7 times, a two 8 times, a three 5 times, a four 9 times, a five 8 times, and a six 5 times. What is the experimental probability of rolling an odd number?
February 20, 2015

Math
A spinner is split up into 4 colored areas of the same size: red, blue, green, and yellow. What is the theoretical probability of the spinner landing on one of these four colors?
February 20, 2015

Math
A standard deck of cards contains 52 cards. Of these cards there are 13 of each type of suit (hearts, spades, clubs, diamonds) and 4 of each type of rank (A – K). Four cards are pulled in order from this deck of 52 playing cards. What is the probability that the cards ...
February 19, 2015

Math (Probability)
A standard deck of cards contains 52 cards. Of these cards there are 13 of each type of suit (hearts, spades, clubs, diamonds) and 4 of each type of rank (A – K). Two cards are pulled in order, without replacement from this deck of 52 playing cards. What is the ...
February 19, 2015

Finance
Bob bought an 8.5% annual coupon bond at par. One year later, he sold the bond at a quoted price of 98. During the year, market interest rates rose and inflation was 3%. What real rate of return did Bob earn on this investment?
February 19, 2015

French
# 2: Sonyra a demande une tomate, mais il lui a donne un ognion. #3- Daniel a demande du pate, mais il lui a donne des oeufs #4- Raphael a demande un poviron rouge, mais il lui du champignons.
February 18, 2015

French
Thanks!
February 18, 2015

French
3 - Au marché The new employee can't get anyone's order right. Say what each customer asked for and what the employee gave them. Modèle-je / des frites J'ai demandé des frites, mais il m'a donné du pain. 1. Malika / une pêche ...
February 18, 2015

math
Point R is located in quadrant 1. Point S is located in quadrant 3.
February 18, 2015

algebra
An artist framed a rectangular picture. The dimensions of the frame are 4x+3 and 3x+5. He is going to place the picture with the border of 2 inches. Then he wants to paint the border. What is the area he has to paint?
February 17, 2015

Physical Science
A rock is dropped off a 20m tall cliff. How long does it take to get to the bottom of the cliff? What is the instantaneous velocity right before it hits the bottom of the cliff?
February 17, 2015

geometry
Jamie needs to find the missing angle of a right triangle with the third angle measuring 62 degrees. What is the measure of the third angle of the triangle?
February 10, 2015

chemistry
Calculate the energy of a photon of wavelength 3.1 µm with that of wavelength 0.166 nm. What I Got: 3.1 µm photon: 6.36x10^22j 0.166nm photon: 1.23x10^19j Also, what region of the electromagentic spectrum would each of these measurements belong to?
February 8, 2015

Does <= means less than or equal to
February 8, 2015

To qualify for a store discount, Clay's soccer team must spend at least \$560 for new jerseys. The team needs 20 jerseys. Write and solve an inequality to represent how much the team should spend on each jersey to qualify for the discount.
February 8, 2015

Physics
whats a fbd
February 7, 2015

Physics
i need help
February 7, 2015

Physics
i cant put the image : ((((
February 7, 2015

Physics
what is that ?
February 7, 2015

Physics
A vector has magnitude 58.0 units and is inclined to the positive axis of x at 42.0°. Vector has magnitude 36.0 units and is inclined to the positive axis of x at 121°. Vector has magnitude 40.0 units and is inclined to the positive axis of x at 53.0°. Use the ...
February 7, 2015

Physics
A river flows at a speed of 4.60 m/s. A boat, capable of moving with a speed of 5.80 m/s in still water is rowed across the river at an angle of 53.0° to the river flow. Calculate the resultant velocity with which the boat moves and the angle that its resultant motion ...
February 7, 2015

Physics
An airplane has to fly eastward to a destination 856 km away. If wind is blowing at 18.0 m/s northward and the air speed of the plane is 161 m/s, in what direction should the plane head to reach its destination?
February 7, 2015

Physics
The blocks A and B are connected by a piece of spring. Block B rests on an inclined plane of 40° and block A hangs vertically. The coefficient of kinetic friction between block A and the inclined plane is 0.29. Calculate the acceleration of the system if the mass of block ...
February 7, 2015

Physics
An athlete runs 2.76 km east, then turns south and runs another 0.85 km. What is the magnitude of his displacement?
February 7, 2015

Physics
Find the magnitude of the sum of two forces, one 24 N and the other 9 N, when the angle between them is 60.0o.
February 7, 2015

Physics
What should be the angle between two vectors of magnitudes 4.10 and 4.40 units, so that their resultant has a magnitude of 3.90 units?
February 7, 2015

Physics
The blocks A and B are connected by a piece of spring. Block B rests on a smooth inclined plane of 35° and block A hangs vertically. Calculate the acceleration of the system if the mass of block A is 1.06 kg and that of block B is 6.4 kg
February 7, 2015

Algebra 2
Simplify each expression. 1+sqrt(3) ______________ sqrt(3)-sqrt(2) *this is a division radical expression please show work!!
February 7, 2015

Algebra 2
Simplify this expression sqrt(3y^3)*sqrt(4xy^4)*sqrt(6x^5y^2) Please show work!!!
February 7, 2015

physics
An arrow is shot straight upward into the air and it returns to the ground with a speed of 28m/s. What was the maximum height reached by the arrow?
February 5, 2015