Total # Posts: 1,884
a drug is supplied as a 20 mg/ml solution in a 50 ml vial. you need to make 15 ml of a 10 mg/ml solution. how much concentrate and how much diluent are needed to obtain the desired final volume?
July 9, 2014
A year ago, the Alpine Growth Fund was being quoted at an NAV of $21.50 and an offer price of $23.35; today, its being quoted at $23.04 (NAV) and $25.04 (offer). Use the approximate yield formula or a handheld financial calculator to find the rate of return on this load ...
June 23, 2014
An investor in the 28% tax bracket is trying to decide which of two bonds to select: one is a 5.5% U.S. Treasury bond selling at par; the other is a municipal bond with a 4.25% coupon, which is also selling at par. Which of these two bonds should the investor select? Why?
June 22, 2014
In the figure, a uniform ladder of weight 200 N and length 10 m leans against a perfectly smooth wall. A firefighter of weight 600 N climbs a distance x up the ladder. The coefficient of static friction between the ladder and the floor is 0.50. What is the maximum value of x ...
May 11, 2014
I haven't had a chance to meet with my Spanish professor about my composition and I need to turn it in soon. It's basically just a short past narration (15 sentences) using only the preterite and imperfect. If someone could read through it and let me know what things I...
May 3, 2014
I can't seem to figure out the name of this organic molecule. I know it's an amine, but that's it. There are two methyls (CH3) attached to a CH, followed by (in order) NH, CH2, CH2, CH2, and CH3. (ignore the ^^^, I had to use them so the atoms would line up...
April 9, 2014
My "picture" of the molecule didn't work. Hopefully, this will work better (~ represents a triple bond and ignore the ```) ````````CH3 ````````CH2 HC ~ C - C - CH2 - CH3 ````````CH2 ````````CH3
April 9, 2014
I'm having trouble naming this organic chemistry compound. (I'm not sure how to include a picture in this, so I'll try my best to explain it in words and attempt to type it out) The full formula is C9H16. It's an alkyne and the longest carbon chain is 5 carbons...
April 9, 2014
Earthquakes are essentially sound wavescalled seismic wavestraveling through the earth. Because the earth is solid, it can support both longitudinal and transverse seismic waves. The speed of longitudinal waves, called P waves, is 7800m/s . Transverse waves, called...
April 7, 2014
"Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of the following aqueous solution: CuBr2(aq)" Possible oxidation reactions: 1. 2Br- -> Br2 + 2e- = -1.09 2. 2H2O -> O2 + 4H+ + 4e- = -1.23 Possible reduction ...
April 2, 2014
#1 Is C. Industry. #3 It's not D. In the study guide it says to prepare the introduction and overview last. It's not B. I used that in my test and it was wrong. I'm stuck between C and A. I don't know 2 or 4.
February 11, 2014
guess my rule with two rules. Having such as hard time understanding this and would like to be able to explain to my 2nd grader! home wor sheet has 2 circles joined togeather, rule A has 2 girls in it with glasses, in the middle there is another girl with glasses, in rule B ...
February 4, 2014
A 0.20-kg object is attached to the end of an ideal horizontal spring that has a spring constant of 120 N/m. The simple harmonic motion that occurs has a maximum speed of 2.0 m/s. Determine the amplitude A of the motion.
January 25, 2014
Chemistry Check Please! ?Fixed
A solution is prepared by dissolving 3.44 g of sucrose, C12H22O11, in 118 g of water. a) What is the molality of the resulting solution? b) What is the mole fraction of water in this solution? B) moles of h2o=118g/18(g/mol)=6.548 mol moles of c12h22O11= 3.44g/342.3(g/mol)=0....
January 17, 2014
Chemistry Check Please!
A solution is prepared by dissolving 3.44 g of sucrose, C12H22O11, in 118 g of water. a) What is the molality of the resulting solution? b) What is the mole fraction of water in this solution? B) moles of h2o=118g/18(g/mol)=6.5556 mol moles of c12h22O11= 3.44g/342.3(g/mol)=0....
January 16, 2014
Chemisty Check Please!
B) moles of h2o=118g/18(g/mol)=6.5556 mol moles of c12h22O11= 3.44g/342.3(g/mol)=0.10049 mol 6.5556 mol/(6.5556 mol + 0.10049 mol= 0.984902 mol A) M= (0.10049)/(0.00344 kg + 0.118 kg)= 0.82749 m c12h22O11
January 14, 2014
A solution is prepared by dissolving 3.44 g of sucrose, C12H22O11, in 118 g of water. a) What is the molality of the resulting solution? b) What is the mole fraction of water in this solution?
January 14, 2014
There were 10 more boys than girls at an outing. Each boy was given 3 sweets and each girl was given 4 sweets. A total of 156 sweets were given to the children. How many girls were there at the outing?
January 1, 2014
Solve the given equation. (Enter your answers as a comma-separated list. Let k be any integer. Round terms to three decimal places where appropriate. If there is no solution, enter NO SOLUTION.) 5 sin^2(x)- 21 sin(x)+ 4 =0
November 27, 2013
A spotlight on the ground is shining on a wall 12m away. If a woman 2m tall walks from the spotlight toward the building at a speed of 0.6m/s, how fast is the length of her shadow on the building decreasing when she is 2m from the building?
October 30, 2013
If the mass of a planet is 0.571 times that of the Earth and its radius is 0.787 times that of the Earth, estimate the gravitational field g at the surface of the planet. The gravitational acceleration on Earth is 9.8 m/s2. Answer in units of m/s2
October 29, 2013
In the Bohr model of the hydrogen atom, the speed of the electron is approximately 2.1 × 106 m/s. Find the central force acting on the electron as it revolves in a circular orbit of radius 4.51 × 10−11 m. Answer in units of N
October 29, 2013
The bottle was previously opeedn, thus altering the water content. This is because hydrates do not keep their stoichiometric ratio of cations and anions to water molecules. Hope this helps.
October 8, 2013
Just break it down 4 (10's)= 10+10+10+10 = 4*10 = 40 5 (10's)= 10+10+10+10+10 = 5*10 = 50 9 (1's)= 1+1+1+1+1+1+1+1+1= 9*1 = 9 You can also rewrite the problem this way 40 < x < 50 This means the number has to be between 40 and 50, but it must also have 9 ones...
September 25, 2013
A statue is 8 feet tall. The display case for a model of the statue is 18 inches tall. Which scale allows the tallest model of the statue that will fit in the display case. A 1 inch : 2 inches B 1 inch : 7 inches C 1 inch : 5 inches D 1 inch : 10 inches
September 16, 2013
two objects move toward each other collide and separate. there was no net external force acting on the objects but some kinetic energy was lost. is momentum conserved ? what is the explanation ?
August 16, 2013
Why all enzyme work well in their own optimum temperature and optimum pH ? i need more explanation about why different enzyme have different optimum temperature and different optimum pH to react. i hope to get a long explanation for my essay that contain 5 marks.
July 31, 2013
According to the Professor Sandel, if judgments about the good are unavoidable in debates about justice and rights, is it possible to reason about the good (these judgments about the good)? a) If reasoning about the good means that you must have a single principle or rule or ...
July 31, 2013
as i have known that centripetal force is directly proportional to the angular speed square. so, what is the relationship between angular speed and centripetal force ? when centripetal force increase, does angular speed increase too? i need more explanation.
July 29, 2013
sorry, wrong typo... the answer is when the water level is lower, the air in the glass tube. the changing of the L is to match the natural frequency of the air column inside the glass tube with the tuning fork that vibrate at fixed frequency. when the matching is achieve, the ...
July 11, 2013
Henry's Law says: Pressure(gas)=(Henry's Law Constant)(Molarity of the gas) we are looking for Molarity so we can rewrite the above equation as Molarity of the gas=Pressure(gas)/(Henry's Law Constant) so M=1.95 bar/29.4 barM-1 the bar units cancel...
July 5, 2013
An engine absorbs 2000j of heat from a hot reservoir and expels 750j to a cold reservoir during each poerating cycle, (i)what is the efficiency of the engine (ii)How much work is done during the cycle? (iii)What is the power output of the engine if each cycle last for 0.5 ...
July 4, 2013
(Q1)A gas occupies a certain volume at 27c.If it is heated at constant pressure, its volume is exactly doubled at a temperature of. (a)54c(b)219c(c)327c(d)600c (Q2)If the specific heat capacity of water initially is4.2000/kg/k and the difference in temperature of water between...
July 3, 2013
(Q1)the temperature at which the tungsten filament of a 12v and 36w lamp operates is 1730c.If the temperature coefficient of resistance of tungsten is 0.006/k, find the resistance of the lamp at room temperature of 20c (a)10.00(b)0.45ohms(c)0.39ohms(d)4.00ohms (Q2)At what ...
July 3, 2013
(Q1)A wire of cross- sectional area of 0.00006m2 and length 50cm stretches by 0.2mm under a load of 3000n.Calculate the Young's modulus for the wire (a)80000000000Nm-2(b)125000000000Nm-2(c)25000000000Nm-2(d)5000000000Nm-2 (Q2)a square plate of side 10cm is made of a metal ...
July 3, 2013
(Q1)calculate the electric power which must be supplied to the filament of a light bulb operating at 3000k. the total surface area of the filament is 0.000008m2 and iits emissivity is 0.92.(a)20.3w (b)33.8w(c)46.4w(d)56.7w (Q2) calculate the change in internal energy of 2kg of...
July 3, 2013
an ungraduated mercury thermometer attached to a millimeter scale reads 22.8mm in ice and 242mm in steam at standard pressure. What will the millimeter read when the temperature is 20
July 2, 2013
paychecks each week will be as follows : $325 x 40 = $13,000 (gross earnings /week) $13,000 x 0.062 = $806 (total combined social security) $13,000 x 0.0145 = $188.50 (total medicare taxes) social security : 806 medicare: 188.50
June 8, 2013
A box is placed 50 cm away from a double convex lens. The image is on the opposite side of the lens, is inverted and 50 cm away from the lens. find: a)the focal length of the lens. b)the height of the image. c) using the focal length that you found, how far from the lens would...
May 30, 2013
1- increase 1000 dollars by 10% then decrrese ur answer by 10% wat do u notice? 2- my parents increased my pocket money by 10% then 3 months later increased it by further. 10%'. My father said there was an increase of 21% , can u explain this?
May 25, 2013
You are building a rectangular deck. The area of the deck should be 250 ft squared. You want the length of the deck to be 5 ft longer than twice its width. What should the dimensions of the deck be? My work: 250=2x(x+5) Is this correct so far?
May 22, 2013