Saturday
February 25, 2017

# Posts by David

Total # Posts: 2,226

PHYsics
A centrifuge for separation of sugar crystals in molasses must exert a force of 6 N/g. If the filter drum has a radius of 350 mm, determine the required speed in the revolution per minute I tried the following F = 6 = 10^-3*a a = 6000 = ω^2*r
April 14, 2015

math
A city park employee collected 600 cents in nickels, dimes and quarters at the bottom of a wishing well. There were 10 nickels and a combined total of 25 dimes and quarters. How many dimes and quarters were at the bottom of the well? I know the answer but need help with what ...
April 9, 2015

Math
(-24,-15)
April 3, 2015

physics
A copper atom has 29 electrons revolving around the nucleus. A copper ball has 4x10^23 atoms. What fraction of the electrons be removed to give the ball a charge of +9.6uC?
March 31, 2015

Pschology 202
well- being
March 29, 2015

Chemistry
I, II, III
March 18, 2015

Math
You run 21 miles in 6 days. find the rate.
March 12, 2015

Managerial Accounting
Waterways is thinking of mass-producing one of its special-order sprinklers. To do so would increase variable costs for all sprinklers by an average of $0.70 per unit. The company also estimates that this change could increase the overall number of sprinklers sold by 10%, and ... March 11, 2015 Accounting Waterways is thinking of mass-producing one of its special-order sprinklers. To do so would increase variable costs for all sprinklers by an average of$0.70 per unit. The company also estimates that this change could increase the overall number of sprinklers sold by 10%, and ...
March 11, 2015

chemistry
10 l of a solution containing 1.5 moles of HI
March 10, 2015

Physics
Consider an air-bubble level that is sitting on a horizontal surface. Initially, the air bubble is in the middle of the horizontal glass tube. (a) If the level is pushed and a force is applied to accelerate it, which way would the bubble move? Which way would the bubble move ...
March 3, 2015

Physics
A 100 kg crate rest at the back of the bed of a pick up truck. The length of the crate is 1 m in the length of the bed is 4 m. There is no friction between the bed of the truck in the crate. If the truck is traveling at 25 m/s just before it hits the wall, how long before the ...
March 3, 2015

scdience
the density of gas was done twice, but with the tablet and 15 cm^3 of water in each case.When the rubber tube was placed as shown , 435 cm^3 of gas was collected. When the tube reached only slightly beyond the mouth of the bottle, only 370 cm^3 of gas was collected. The change...
March 2, 2015

math
first string sports can purchase sneakers for $450 per dozen less trade discounts of 14/12 from ideal shoes. Fancy footwear is offering the same sneakers for$435 less trade discounts of 18/6. Which supplier offers a lower net price? would i be correct if i said first string ...
February 27, 2015

math
Would I be correct if I put $54.58 as my answer, Steve? February 26, 2015 math okay i get that so would i be correct if i did 889.00*61.4? since trade discount equals list price * trade discount percentage? February 26, 2015 math A watch with a list price of$889.00 is sold by a wholesaler at a net cost of $545.75. Find the single trade discount rate being offered. round to the nearest tenth of a percent To solve this i did 545.75 divided by 889.00 that gave me 0.61389 which comes out to 61.4% if i ... February 26, 2015 math so would i be correct if i got$155.56 as an answer, Lucina?
February 26, 2015

math
The list price of a set of fine china is $345.70 and the trade discount is 55%. Find the net cost. I did$345.70 *.55= 190.14 that gives me the trade discount. i'm confused on how i then find the net cost, do i subtract 190.14 from 345.70 to get the net cost?
February 26, 2015

math
The ratio is 2:7>their mom gives each of them the 15 marbles and now David has twice as many marbles as Charlie.How many marbles does each boy have
February 24, 2015

math
The ratio of Juma’s and Akinyi's earnings was 5:3. Juma’s earnings rose to shilling 8400 after an increase of 12%. Calculate the percentage increase in Akinyi’s earning given that the sum of their new earnings was shilling 14100. (b) Juma and Akinyi ...
February 24, 2015

Business Math
Find the ordinary interest to the nearest cent. $19,000 at 12% for 101 days February 23, 2015 math In the geometric progression, the first is a and the common ratio is r. The sun of the first two terms is 12 and the third term is 16 Determine the ratio (ar^2)/(a+ar) If the first term is larger than the second term, find the value of r. February 17, 2015 math A perpendicular to the line -4x +3 = 0 point (8, 5). Determine its equation x = 4/3 undefined y = 5 February 17, 2015 Math A fuel dealer makes a profit of shillings 520 for every 1000 liters of petrol sold and shillings 480 for every 1000 liters of diesel sold. In a certain month the dealer sold twice as much diesel as petrol. If the total fuel sold that month was 900,000 liters, find the dealer&#... February 17, 2015 science In an experiment to determine the speed of sound, two observers, A and B, were stationed 5.0 km apart. Each was equipped with a gun and a stopwatch. Observer A heard the report of B's gun 15.5 s after seeing it's flash. Later, A fired his gun and B heard the report 14.... February 16, 2015 physics h=v_0+at^2 h=0+(-9.8)t^2 h=96.4(t) .45h=96.4(1) h=96.1/0.45 h=213.422ft February 6, 2015 math its no proof but you could see the results are: 3/2, 6/5, 15/14,42/41,123/122,366/365,1095/1094,3282/3281,9843/9842. as you could see it comes closer and closer to 1 therfore its limit is 1. February 1, 2015 math I can answer the second part. Obviously it converges to 1. But i do not know how to prove it... I do not know if it is legit but maybe since you know the limit is 1 use definition: For every n>N |a_n-1|<epsilon and prove this way. February 1, 2015 ELA FAST HELP URGENT It's A. Limericks are witty poems that are about 5 lines long. There was a young lady of Niger who smiled as she rode on a tiger; They returned from the ride with the lady inside, and the smile on the face of the tiger. January 30, 2015 physics At the instant the traffic light turns green, an automobile that has been waiting at an intersection starts ahead with a constant acceleration of 2.10m/s2 . At the same instant, a truck, traveling with a constant speed of 15.1m/s , overtakes and passes the automobile. How far ... January 29, 2015 physics A rod with length L and mass m stand on a frictionless table. a ball with mass m and speed u cimped perpendicular to the rod a distance x from the bottom of the rod and sticks to it. what is the angular velocity of the rod+ball after the collison? I need help on how to solve ... January 27, 2015 math if your body releases about a liter of saliva a day how many years to release a kiloliter January 25, 2015 math what are all the rectangular pens you can build with 16 yds of fencing January 25, 2015 Physics A car slows down from a speed of 24.0m/s to rest in 9.0s, How far did it travel in that time? January 24, 2015 Physics car leaves skid mark 72m in length with a deceleration speed of 7.20m/s^2. what was the initial speed prior to braking? January 24, 2015 Physics A car leaves skid marks 72m in length. The deceleration is 7.2m/s^2. What is the speed of the car before braking? January 23, 2015 Chemistry How much energy (in kilojoules) is released when 15.2g of steam at 114.5∘C is condensed to give liquid water at 63.5∘C? The heat of vaporization of liquid water is 40.67 kJ/mol, and the molar heat capacity is 75.3 J/(K⋅mol) for the liquid and 33.6 J/(K⋅... January 21, 2015 accounting did you ever get your answer January 13, 2015 english Write a narrative essay that ends with 'once beaten, twice shy' January 13, 2015 physics A heavy table of mass M is vibrationally isolated by being hung from the ceiling by springs, so that its frequency of vertical oscillation is \omega_0 (take \omega_0 to be 2\pi/sec, a typical value). Assume now that the ceiling vibrates vertically with amplitude A at frequency... January 8, 2015 Math 1) Prove that for every x>=0 and 0<a<1 x^a-ax<=1-a 2)prove that for 0<=x<=1: x^m*(1-x)^n<= (m^m*n^n)/((m+n)^(m+n)) can someone please guide/help me in about how to solve and or approch these questions? (I know I have already posted it before but i think it... January 7, 2015 Math 1) Proove that for every x>=0 and 0<a<1 x^a-ax<=1-a 2)prove that for 0<=x<=1: x^m*(1-x)^n<= (m^m*n^n)/((m+n)^(m+n)) can someone please guide/help me in about how to solve and or approch these questions? January 7, 2015 Science Yes, the answers are: 1.C 2.B 3.B 4.D January 6, 2015 programming It is a computer course for physicists. Therfore i do not study programming as my main course. also i have missed a few lessons, therfore i do not even know where to begin. December 26, 2014 programming – Define a structure called Object which includes three doubles specifying the object’s mass, volume and density. – Create an array of 10 Objects. – Define the function void scanobjectsdata(struct Object objects[], int size) that scans from the input and ... December 26, 2014 AP Calc Find the value of c which satisfies Rolle’s Theorem for the function f(x)=sin(x²) on (0,√π). December 20, 2014 Physics A 283 g air track glider moving at 0.69 m/s on a 2.4 m long air track collides elastically with a 467 g glider at rest in the middle of the horizontal track. The end of the track over which the struck glider moves is not frictionless, and the glider moves with a coefficient of... December 14, 2014 Physics A 283 g air track glider moving at 0.69 m/s on a 2.4 m long air track collides elastically with a 467 g glider at rest in the middle of the horizontal track. The end of the track over which the struck glider moves is not frictionless, and the glider moves with a coefficient of... December 12, 2014 Calculus Thanks! December 10, 2014 Calculus This is a calculus homework question but in reality the problem here is understanding the algebra. Find the Critical Numbers of f(x) = x^(3/5)(4-x) The product rule gives -x^(3/5) + (12-3x)/(5x^(2/5) My booklet explains that simplifying this gives you 12-8x / (5x^(2/5). How ... December 10, 2014 Calculus in the equation a/(1-r) December 8, 2014 Calculus so a is the first term in the series and r is the term that is being reused over and over again ? December 8, 2014 Calculus So this one is confusing me: limit of n as it approaches infinity of (n{SIGMA}i=1) (1/(2^i) *the n is on top of the sigma notation and i=1 is at the bottom. I understand that 'i' would equal (n(n+1))/2 however the algebra from there confuses me. December 8, 2014 Calculus I am trying to solve the following L'hopital's limits question below: lim x -> 0 from the positive direction of ( 5^(sin(x)) - 1 )/ (x) December 8, 2014 Calculus L'hopital's question below: lim x -> 0 from the positive direction of ( 5^(sin(x)) - 1 )/ (x) December 7, 2014 AP Chemistry What percent (by mass) of granulated sugar is fructose, and what percent of it is sucrose? Background: We are doing a colligative properties lab in my class where we are to add 20 grams, 40 grams, 60 grams, and 80 grams of sugar to 100 grams of water, and use the change in the... December 6, 2014 AP Chemistry What is the Van't Hoff Factor of MgSO4*7H2O? We're doing a colligative properties lab at my school where we dissolve various amounts of MgSO4 in 100 grams of water. What value/range of values should I expect the Van't Hoff Factor to be? December 6, 2014 Physics You have a brass ring of inside diameter 10.00 cm that is at 20.0oC. You want to slip this ring over an aluminum rod that is at 20.0oC and has a diameter of 10.01 cm. a. To what temperature do you have to heat the ring to slip it over the rod? b. Once you have the ring over ... December 4, 2014 Biology Which alga is most closely related to plants? A) Chara B) Kelp C) Ulva D) Diatom E) Euglena I think it's chara, because it is green algae, but I'm not sure. Can you explain to me why it is or not? November 20, 2014 Math 23 multiplied by 12= 276 276-15= 261 The answer is 261 November 20, 2014 physics A person is stranded and sitting 45m above the ground on the ledge of the cliff. of a safety rope is launched upward at an angle of 50 degrees above the horizontal at a distance of 60m away, what is the initial velocity of the rope so that it reaches the stranded person? November 19, 2014 physica help A thermally insulated vessel containing 100 grams of ice at 0 degrees Celsius . Water at 55 degrees celsius is poured and after some time , the system reaches the equilibrium at a temperature of 10 degrees Celsius. That amount of water in grams was placed . ( heat fusion... November 17, 2014 Math In a coordinate plane, Brittany labeled the coordinates for point m as (-31/2,2). Sade tells Brittany to reflect point m over the x axis to point r. What are the coordinate of point r? November 16, 2014 physical help the positions of two particles A and B are P1 (3,4) in meters and P2 ( -3, -4 ) meters respectively. Meters the position A with respect to B is: November 14, 2014 physics A space station shaped like a giant wheel has a radius of 1.00 x 10^2 m and a moment of inertia of 5.00 x 10^8 kgm^2. A crew of 150 lives on the rim, and the station is rotating so that the crew experiences an apparent acceleration of 1.0g. When 120 people move to the center ... November 11, 2014 physics a 2100 kg car starts from rest and accelerates at a rate of 2.6 m/s for 4 sec. assume that the force acting to accelerate the car is acting in the same direction as its motion. how much work has the car done? m=2100 kg w=fd v1=0 f=ma t=4 sec d=t+1/2at(squared) a=2.6 m/s2 November 11, 2014 PLEASE HELP ASAP Language Arts I believe it's A correct me if I'm wrong though.* November 10, 2014 PLEASE HELP ASAP Language Arts I believe it's B correct me if I'm wrong though. November 10, 2014 Physics A moving 4.5 kg block collides with a horizontal spring whose spring constant is 226 N/m (see figure). The block compresses the spring a maximum distance of 8.0 cm from its rest position. The coefficient of kinetic friction between the block and the horizontal surface is 0.47... November 9, 2014 Engineering science a roller of diameter 1.5 m has a mass of 450 kg; it is pulled by a handle attached to its centre. Find the minimum force to pull up a step which is 250 mm high if the roller handle makes an angle of 30o with the horizontal November 9, 2014 math Rounded to what? Currently it is rounded to the nearest thousandth. If you were to round it to the nearest hundredth it would be 0.08 and to the nearest tenth 0.1. November 6, 2014 Intermediate Algebra (-9)1/2 = -4.5 which is a real number. Unless you're talking about square roots? November 6, 2014 chemistry The trend for electron affinity on the periodic table is that it increases from the bottom left of the table to the top right. He>I>Te>Bi>Na Should be the order. November 6, 2014 Science HELP Due to the conservation of mass, the mass of the reactants is equal to the mass of the products. Mass(A) + Mass(B) = Mass Solid Product 10g + 17g = 27g Mass(beaker) = Mass(Beaker + product) - Mass (product) So Mass(Beaker) = 32g - 27g = 5g So your answer is "A. 5g." November 6, 2014 Math I'm not entirely sure what you are asking, but I'll give it a shot. (5x4) + (1x4) is NOT the same as 6x8. Lets look at it in detail: 6x8 = 48 5x4 = 20 and 1 x 4 = 4 20 + 4 = 24 which is not 48. The most you could do is some factoring, but you have to make sure your ... November 6, 2014 Science HELP Zn(s) + 2HCl(aq) ---> ZnCl2(aq) + H2(g) It is D, but don't forget to include the extra hydrogen atoms, or else the equation violates the law of conservation of mass. In this case, hydrogen gas (H2) is formed. November 6, 2014 Science Due to the conservation of mass, the mass of the reactants is equal to the mass of the products. Mass(A) + Mass(B) = Mass Solid Product 10g + 17g = 27g Mass(beaker) = Mass(Beaker + product) - Mass (product) So Mass(Beaker) = 32g - 27g = 5g So your answer is "A. 5g." November 6, 2014 math 7 books to wrap, each 5/6 of a foot long. how long a roll needed 7x12 =84 5/6x7=35/42? November 6, 2014 Algebra HELP! Part A: Lets say the number any student chooses is 'x'. We need to perform operations to get to 'x-1'. There are many possibilities for this. For example, consider the following scenario where the student is 's' and the teacher is 't'. I'll ... November 6, 2014 physics A particle undergoes three successive displacement in a plane as follows 4m southwest, 5m east, 6m in a direction 60 degree north of east (a) draw an apropraite vector diagram to represcent the displacement (b) detarmine the displacement that would be required to bring the ... November 4, 2014 physics A hollow 0.358 kg sphere rolls without slipping down an inclined plane that makes an angle of 41.0o with the horizontal direction. The sphere is released from rest a distance 0.734 m from the lower end of the plane. a. How fast is the hollow sphere moving as it reaches the end... November 3, 2014 physics A hollow 0.358 kg sphere rolls without slipping down an inclined plane that makes an angle of 41.0o with the horizontal direction. The sphere is released from rest a distance 0.734 m from the lower end of the plane. a. How fast is the hollow sphere moving as it reaches the end... November 3, 2014 Physics Creating Z_0 boson via symmetric beams a. Z0 boson has a rest mass energy of 91.187 GeV. It is produced in collisions of positrons and electrons. e^- + e^+ to Z_0 How much kinetic energy must the positrons and electrons in symmetric colliding beams have to produce the Z0 boson... October 30, 2014 Physics Creating Z_0 boson via symmetric beams a. Z0 boson has a rest mass energy of 91.187 GeV. It is produced in collisions of positrons and electrons. e^- + e^+ to Z_0 How much kinetic energy must the positrons and electrons in symmetric colliding beams have to produce the Z0 boson... October 30, 2014 Physics A 0.250-kg ice puck, moving east with a speed of 5.26m/s , has a head-on collision with a 0.990-kg puck initially at rest. Assume that the collision is perfectly elastic.What is the speed of the 0.250-kg puck after the collision? October 29, 2014 Chemistry The reaction of iron and water vapor results in an equilibrium reaction, 3 Fe(s) + 4 H2O(g) ¡ê Fe3O4(s) + 4 H2(g) and an equilibrium constant of 4.6 at 850¡ÆC. What is the concentration of Hydrogen present at equilibrium if the reaction is initiated ... October 28, 2014 physics A figure skater is spinning with an angular velocity of +10 rad/s. She then comes to a stop over a brief period of time. During this time, her angular displacement is +5.8 rad. Determine (a) her average angular acceleration and (b) the time during which she comes to rest. October 27, 2014 Biology Compare ad contrast indirect versus direct values of biodiversity and provide two examples? October 24, 2014 physics A small pumpkin of mass 2.22 kg is dropped from rest from a height of 2.87 m. The pumpkin rebounds from the ground to a height of 1.12 m. a. With what speed does the pumpkin hit the ground? b. With what speed does the pumpkin leave the ground? c. What impulse was given to the ... October 24, 2014 physics vf1= ((m1-m2)/(m1+m2))(v1) vf2= ((2m1)/(m1+m2))(v1) October 23, 2014 business math The sweet candy shop buys 600 pounds of chocolate covered strawberries at$5.59 per pound. If a 10% spoilage rate is anticipated, at what price per pound should the strawberries be sold in order achieve a 60% markup based on cost?
October 20, 2014

Estimating decimal quotient
180.8/6=180/6=30 18.2/11=20/10=2 55/10.7=50/10=5 0.6/5=1.0/5=0.2 145/0.3=145/3=15 60/5.9=60/6=10 1.8/20=2.0/20=0.1
October 19, 2014

Estimating decimal quotient
Use compatible to find the following quotient 180.8 divided by 6 182divided by 11 55divided by 10.7 117.8divided by 0.12 0.6 divided by 5 145 divided by 0.3 60 divided by 5.9 1.8 divided by 20
October 19, 2014

Business Math
Jeanna wants to buy a new boat for her family. She has two payment options. The first option is to pay a cash payment of $7,200. The second option is to finance the boat with a three year installment loan. The loan requires a 10% down payment and 36 equal monthly payments of$...
October 19, 2014

Biology
Compare and contrast indirect versus direct values of biodiversity, and provide examples.
October 17, 2014

Math
Every item in the Just a Dollar store is priced at $1.00. When Mary Jo opens the store, there is$122.00 in the cash register. When she counts the money in the cash register at the end of the day, the total is \$1,065.95. If the sales tax rate is 8.5%, how many items were sold ...
October 13, 2014