craig
Popular questions and responses by craig
chemistry
Strong base is dissolved in 665 mL of 0.400 M weak acid (Ka = 3.69 × 105) to make a buffer with a pH of 3.94. Assume that the volume remains constant when the base is added. HA(aq) + OH(aq) > H2O(l) + A(aq) Calculate the pKa value of the acid and
asked on July 8, 2012 
Algebra 1
The upward velocity of the water in the stream of a particular fountain is given by the formula v = 32t + 28, where t is the number of secondds after the water leaves the fountain. While going upward, the water slows down until, at the top of the stream,
asked on October 11, 2007 
math
a rectangular pen is to be constructed alongside a barn using 120 feet of fencing. the barn will be used for one side of the pen. What should the dimensions of the pen be to maximize its area. ***Can not use calculus. This is a 9th grade question
asked on September 28, 2011 
Calculus
For an object whose velocity in ft/sec is given by v(t) = 3t2 + 5, what is its displacement, in feet, on the interval t = 0 to t = 2 secs? 6.607 2 2.303 2.303
asked on June 19, 2018 
Calculus (related rates)
A ladder 13 meters long rests on horizontal ground and leans against a vertical wall. The foot of the ladder is pulled away from the wall at the rate of 0.4 m/sec. How fast is the top sliding down the wall when the foot of the ladder is 5 m from the wall?
asked on March 21, 2017 
college math
How many different committees can be formed from 9 teachers and 39 students if the committee consists of 2 teachers and 3 students? In how many ways can the committee of 5 members be selected?
asked on March 24, 2013 
math
what is the unit rate for 250 miles in 5 hours
asked on May 11, 2010 
Chemistry
Complete the following equilibrium reactions that are pertinent to an aqueous solution of Ag2CO3. Physical states, s, l, g, and aq, are optional. So far I worked it out to be: Ag2CO3(s) 2Ag^+ + CO3^(2) H2CO3(aq) + H2O(l) H3O^(1+) + (HCO3)^() HCO3^()(aq)
asked on April 6, 2016 
Math
Matt has twice as many stickers as David. If David has d stickers, and Matt gives David 10 stickers, how many stickers does each have in terms of d?
asked on February 20, 2009 
Maths
When you flip a biased coin the probability of getting a tail is 0.6. How many times would you expect to get tails if you flip the coin 320 times?
asked on April 6, 2019 
Trigonometry
Which interval gives an average change of 0 for the function y = 3cos (4πx + π)  3? a) π/3
asked on June 18, 2020 
Calculus (related rates)
Find dy/dt when y = 2x2 + 2x + 4 and dx/dt = 14 when x = 7.
asked on March 21, 2017 
Chemistry
Methane reacts with water to form CO and H2 as follows: CH4(g)+H2O(g)=CO9g)+3H2(g) The value of Kp at 298 k for the reaction is 7.7 *10^24, calculate Kc. If you can please show the steps I would greatly appreciate it. Thank you
asked on December 10, 2013 
chemistry lab
How does the presence of a common ion affect the solubility of a salt? Explain in terms of equilibrium.
asked on July 9, 2012 
ALGEBRA 1
The square of a number is equal to the sum of 21 and 4 times the number. Find the number
asked on January 4, 2012 
algebra
Use the given conditions to write an equation for the line in point'slope form and slopeintercept form. Slope= 5, passing through (9,6) type the pointslope form ot the line Type the slopeintercept form of the line
asked on June 6, 2011 
Math
If I bought an item for $80 on which there was a 30% markup, what is the formula to determine the premarkup price?
asked on July 12, 2010 
Statistics
An investigational drug study is being conducted. The initial screening phase needs to include enough people so that the final (approved) group has at least 10 patients. The probability of a person being approved for the study is .80. what initial sample
asked on June 6, 2009 
IT
high level languages need to be translated. what are two different types of translator? Thank you for using the Jiskha Homework Help Forum. By your question do you mean human vs. mechanical (machine or computerassisted) translation?
asked on February 22, 2007 
math
The average cost to attend a particular university in 1969 was $592 and in 2009 was $17,058. Let y be the average cost in the year x, where x = 0 represents the year 1969. Write a linear equation, in slopeintercept form, that models the growth in cost at
asked on November 17, 2017 
math
The number of boxes on a truck varies directly with the time since the workday began. At 3 hours after the workday began, there are 207 boxes on the truck. How many boxes should we expect there to be on the truck hours after the workday began? Show the
asked on November 14, 2017 
math
Ron would like to have at least $150,000 saved to buy a condo. If he invests $50,000 in an account paying 6.19% interest compounded quarterly, will he reach his goal in 15 years? Show all work to justify your answer and include appropriate units.
asked on November 5, 2017 
Calculus (related rates)
Find dy/dt where y = 2 sqrt(x)4 and dx/dt = 9 when x = 4.
asked on March 21, 2017 
Math
If Tyrone tips Sharqueffa $500 and Daquan tips Watermelondrea $600, how much did the trap house earn that night if Cellularphoniqua (the owner) takes 10% of all tips. Please help
asked on October 6, 2016 
physics
an arrow is shot vertically upward after 2s it is at a height of 36m although this is not necessarily the highest point with what velocity was the arrow shot what is the maximum height reached by the arrow how long is the arrow in flight altogether
asked on July 26, 2016 
physics
the takeoff speed for a large airplane is 180 mi/hr(roughly 80m/s0 the plane is capable of accelerating at a rate of 4m/s^2 assume that the plane starts at rest determine the minimum runway length required for this plane to safely take off a smaller
asked on July 26, 2016 
maths
marcus has a box of chocolates. he eats 1/5 of them. his sister eats 1/3 of the chocolates that are left. there is 24 chocolates left in the box. how many where in the box to start with.
asked on July 1, 2016 
Math
the current population of a city is 45000 and is increasing according to P=45000(1+t)^n and n=number of years. if the rate of increase is 7.5% how long will it take the population to double?
asked on April 25, 2016 
BIOLOGY  HELP URGENT!!!!
How do the following terms relate to one another with respect to a single genetic locus?  Wild Type Allele(s)  Mutant Allele(s)  Gene Product(s)  Population  Genotype  Phenotype  Dominant Allele  Recessive Allele  Individual  Number of different
asked on February 28, 2016 
Math
The costofliving index increased from 100 to 120. What effect does this have on the purchasing power of the dollar?
asked on February 25, 2016 
Math
a 5 foot fence will be built around the perimeter of a 50 foot by 120 foot rectangular lot. if the fence costs $1.80 per linear foot for labor and $.40 per square foot for material, what will be the cost of the fence?
asked on February 24, 2016 
statistics
The average cost per night of a hotel room in New York City is $272 (SmartMoney, March 2009). Assume this estimate is based on a sample of 45 hotels and that the sample standard deviation is $65.
asked on December 9, 2015 
Algebra 2
Show two steps to simplify each of the following expressions, and then calculate the value of each expression. 25 exponent 5/2 81 exponent 7/4
asked on November 3, 2015 
OJTC
if a car was traveling 60 miles an hour and hit and in movable wall instantaneously stopping how many gravities of force would be involved
asked on October 22, 2015 
Geometry
How do you figure the height of a tripod using 28' legs set 7' out from center?
asked on May 18, 2015 
Math
What is the equation 745✖876
asked on October 29, 2014 
algebra
Question: 89 of 111 Leave Questionnaire You need to hire a parttime associate to work 30 hours a week in your store. You have $250 in labor budget for the new associate each week. You just interviewed an excellent candidate for the position who has
asked on June 4, 2014 
math
2x^411x^36x^2+64x+32=0
asked on February 21, 2013 
physics
How much friction force will be required if a car weighing 2100kg traveling at 28m/s rounds a curve of radius 59m banked at a 15 degree angle
asked on September 25, 2012 
physics
in the equation V=sqrt(r*g), what does sqrt stand for?
asked on September 25, 2012 
Math
3x2y=0 xy=1
asked on July 12, 2012 
Geography
What political changes swept through Europe during the second half of the twentieth century?
asked on January 9, 2012 
MATH
the perimter of a rectangle is 20inches and its area is 16 square inches. Find the dimensions of the rectangle. I need help to set up the problem
asked on January 5, 2012 
ALGEBRA 1
The height h is the time of seconds that the ball has been in the air with an initial vertical velocity of 48 feet per second from a height of 5 feet above the ground is given by the equation h=16t^2 + 48t + 5 where t is the time in seconds that the ball
asked on January 3, 2012 
math
Im having a problem understanding this problem so I cant solve it. Bruce knows how many key are on his keyboard, but some don't work. How does Bruce find the number of keys that work? write to explain
asked on December 7, 2011 
Biology
Why does Beta Glucose chains have more weak bonds between the chains than there are between alpha glucose chains?
asked on October 9, 2011 
Managerial Accounting
what management position is responsible for each variance: Sales Materials Labor Overhead General, Selling & Administrative What causes these variances?
asked on April 5, 2011 
Chemistry
A solution is prepared by dissolving 130 g of NaNO3 in 100 g of water at 80°C. The solution is cooled to 0°C. How many grams of compound remain in solution? How may grams of solid are formed?
asked on April 3, 2011 
math
What is 58 rounded to the greatest place value?
asked on February 3, 2011 
Math
The number is between 3 and 10, you can make exactly 3 arrays with this number and it's not 9. What is it?
asked on December 5, 2010 
Math (Calc 1)
Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.3 times the width w of the rectangle (as shown in the figure below). (pictures of a pentagon) If the crosssectional area is A, determine the
asked on November 20, 2010 
Biotechnology
How would you make 450 mL of a 0.250 M NaOH solution?
asked on November 13, 2010 
English
I believe in this sentence: It was the world’s first movie studio. the subject is: movie studio the predicate is: was Am I correct?
asked on September 29, 2010 
English
The first movies were different from today’s films. What is the simple predicate
asked on September 29, 2010 
math
n=1/a1/b solve for b please show all steps
asked on September 16, 2010 
maths.
find the lcd of each setof fractions: 1/2, 1/8, 1/16
asked on September 11, 2010 
Marketing
A manufacturer of AC units realizes a cost of $55.00 for every unit produced. Its total fixed cost is $2,000,000. If the manufacturer produces 500,000 units, calculate its: a. unit cost b. markup price if it desires a 10% returns on sales c. ROI price if
asked on July 12, 2010 
Alge.
Graph the equation using the slope and the yintercept. y=5/3x+2 I need to show the slope and yintercept when I graph.
asked on May 26, 2010 
Math
Is there a difference between solving a system of equations by the algebraic method and the graphical method? Why or why not?
asked on March 10, 2010 
french
can someone check my french essay on pocket money and improve where possible very much appreciated Je recois dix livres d'argent de poche par semaine de mes parents. Pour gagner mon argent de poche je dois aider mes parents a la maison et je dirais que
asked on March 7, 2010 
science
a snowball rolls off the edge of a horizontal roof at a velocity of 7 m/s. what is the speed of the snowball 3 s later?
asked on November 3, 2009 
physics
what is the angular speed of Earth around the Sun in radians per second
asked on October 9, 2009 
law
according to beccaria, the system can reduce the severity of punishment and it can also do what?
asked on September 10, 2009 
Math Statistics
An investigational drug study is being conducted. The initial screening phase needs to include enough people so that the final (approved) group has at least 10 patients. The probability of a person being approved for the study is .80. what initial sample
asked on June 6, 2009 
Algebra
I'm trying to solve this equation for x. .6 = x / x + 20 I can tell that X=30, but how do I prove that mathematically? We can't just plug in numbers, we have to show where we got them from.
asked on February 16, 2009 
trigonometry
show that 1cos^2t divided by sin^2t =TANt
asked on January 30, 2009 
trigonometry
1) show that: 1cos2t divided by sin2t= TANt 2) show that: 1(cos2t divided by (cos x cos)t)= (TAN x TAN)t
asked on January 28, 2009 
Calculus
t: 0 2 5 7 11 12 r'(t): 5.7 4.0 2.0 1.2 0.6 0.5 The volume of a spherical hot air balloon expands as the air inside the balloon is heated. The radius of the balloon in feet is modeled by a twicedifferentiable function of r of time t, where t is measured
asked on November 25, 2008 
Need help fast on calc
original curve: 2y^3+6(x^2)y12x^2+6y=1 dy/dx=(4x2xy)/(x^2+y^2+1) a) write an equation of each horizontal tangent line to the curve b) the line through the origin with the slope .1 is tangent to the curve at P. Find x and y of point P. when plugging y as
asked on November 12, 2008 
Math
How do you do a factor tree for 37?
asked on October 30, 2008 
8th grade
EACH STATEMENT DESCRIBES TWO WORDS THAT WHEN FUSED TOGETHER CREATE A NEW UNRELATED WORD. QUESTION: THIS IS AN ALLOTMENT OF DNA
asked on September 18, 2008 
math
Factoring. 6n^2 +24n 18 Answer: 6(n^2 +4n 3) y^3 y^2 + 3y 3 Answer: (y1)(y^2 +3)
asked on August 21, 2008

physics
9.86
posted on March 19, 2018 
math
donl
posted on February 4, 2018 
math
Sorry.. The number of boxes on a truck varies directly with the time since the workday began. At 3 hours after the workday began, there are 207 boxes on the truck. How many boxes should we expect there to be on the truck 7 1/3 hours after the workday
posted on November 16, 2017 
math
Thanks Scott! Could you possibly break the format down a little more? Did he reach his goal and the units.
posted on November 5, 2017 
Calculus (related rates)
FORMAT WRONG ABOVE.... Correct one is.. Find dy/dt when y = 2x^2 + 2x + 4 and dx/dt = 14 when x = 7.
posted on March 21, 2017 
English
In "Mowgli's Brothers," before he leaves the jungle, Mowgli says, "For the rest, Akela goes free to live as he pleases. Ye will not kill him." What does this show about Mowgli?
posted on January 4, 2017 
12 math
c)3! x 6! The three must remain together but can be in any permutation with the rest. It would be 5! ways if the three books had to be in a certain position.
posted on December 1, 2016 
Math
I think its $990 after Cellularphoniqua takes 10%
posted on October 6, 2016 
Chemistry
Anyone please?
posted on April 7, 2016 
Math
I figured it out. 40 acres = 1320' x 1320'; P=2L + 2W; P=2(1320)+ 2(1320); P=5,280', which is a mile. Run the wire 3x, and it equals 3 miles.
posted on February 25, 2016 
Math
I figured it out. 120100=20, which is the net difference. Divide net difference by the new cost of 120, which equals 16.67 less.
posted on February 25, 2016 
Math
I can't calculate the correct answer.
posted on February 25, 2016 
Math
Thank you for the response. That was the answer that I initially calculated using percentage change; however, the answer is that it was lowered by 16 2/3%. The explanation is that it now takes $6 to buy what used to cost $5. Each dollar is worth 1/6 less.
posted on February 25, 2016 
math
which to end unit is the best choice for measuring the pyramid of a picture on the wall
posted on April 28, 2015 
statistics
78
posted on April 15, 2014 
Math urgent
8x86x=20 2x=28 x=14
posted on December 10, 2013 
Math
5x
posted on July 7, 2013 
how to sketch a graph of..
y=x^21
posted on June 23, 2013 
chemistry lab
Oh that's what it is? Thanks
posted on July 10, 2012 
Statistics
What spinner?
posted on July 8, 2012 
chemistry
thank great help! much appreciated
posted on July 8, 2012 
geometry
a right triangle find the value with 71 5 find x n y answers
posted on January 30, 2012 
ENGLISH
ok fine ,but thanks for the help
posted on January 5, 2012 
ENGLISH
He is right if romeo and juliet get married and the families might come together. The Friar does consent to marry Romeo and Juliet, hoping that the marriage might bring peace between the feuding families. Is this right so far.
posted on January 5, 2012 
Social Studies
Improve Not all early Americans were happy with the Constitution. DemocraticRepublicans, also known as AntiFederalists, opposed the Constitution because they feared the Federal Government would gain too much power... much like King George from whom they
posted on January 4, 2012 
algebra
A farmer decides to enclose a rectangular garden, using the side of a barn as one side of the rectangle. What is the maximum area that the farmer can enclose with 120 ft. of fence? What should the dimensions of the garden be to give the farmer the max
posted on September 28, 2011 
chemistry
stop cheating
posted on November 15, 2010 
English
It
posted on September 29, 2010