Tan
Most popular questions and responses by Tan
calculus
assume that during the first 3 minutes after a foreign substance is introduced into the blood,the rate R'(t) at which new antibodies are produced(in thousands of antibodies per minute) is given by R'(t)=t/(t^2+1) where t is in minutes.find the total
asked on March 19, 2013 
Chemistry
When 0.100 mol CaCO3(s) and 0.100 mol CaO(s) are placed in an evacuated sealed 10.0 L container and heated to 385 K, P(CO2) = 0.220 atm after equilibrium is established. CaCO3(s) CaO(s) + CO2(g) 0.05 atm CO2(g) is then removed from the container. What is
asked on November 18, 2014 
Math
Standing 4ft from the mirror lying on the ground ground, Palmer who's eye height is 5ft 9inches, can reflection the top of the tree. He measures the mirror to be 24ft from the tree. How tall is the tree?
asked on December 30, 2016 
Math
A ribbon is 12 3/8 feet long. Into how many 3/4 foot pieces can it be cut?
asked on October 25, 2016 
physics
As shown in the figure, a bullet of mass m and speed v passes completely through a pendulum bob of mass M. The bullet emerges with a speed of v/2. The pendulum bob is suspended by a stiff rod of length ℓ and negligible mass. 2.1 Derive an expression for
asked on June 8, 2016 
Math
In 1924, the temperature in Fairfield, Montana, dropped from 63 degrees to 21 degrees in 12 hours. What was the average hourly change in temperature. Thank you
asked on October 25, 2016 
Math
A car engine is running at 5000 revolutions per minute. (a) how many revolutions are made in one hour? (b)if this engine uses 10 litres of fuel in one hour, how much fuel, in millilitres,does it use for every revolution?
asked on August 18, 2015 
Science
Acetylene gas combust.how many grams of carbon dioxide and grams of water are produced when 52.0 g of acetylene burns ?
asked on April 11, 2016 
Fianance
A taxexempt bond was recently issued at an annual 8 percent coupon rate and matures 20 years from today. The par value of the bond is $1,000.
asked on December 3, 2015 
Trigo
Find all angles between 0 and 2 phi inclusive which satisfy cot 2z = 1 + cot z
asked on February 10, 2019 
6th grade
Pet Parade: Mr. James has 14 cats, dogs and guinea pigs. What are all the combinations he could have?
asked on October 17, 2014 
Chemistry
In a qualitative analysis, the test for the presence of Cu^2+ ion is the formation of the bright blue complex ion Cu(NH3)42+. What is the equilibrium concentration of Cu2+ when 1.0 mL of 0.200 M Cu^2+ is combined with 1.0 mL of 15.0 M NH3? (Kf Cu(NH3)4^2+
asked on July 8, 2017 
Math
Jared bought a cell phone for $42. Juanita spent 1 1/2 times as much. How much did she spend? Thank you very much!
asked on October 14, 2016 
math
Solve the equation 4x^3 + 32x^2 + 79x + 60 =0 given that the root is equal to the sum of the other two roots. (Hint: set roots as alpha, beta, gamma)
asked on September 4, 2015 
chemistry
what's the discussion for determine BaCl2.2H2O in lab report
asked on June 11, 2014 
Science chemistry
Which compound has the melting point of 23 degree Celsius and boiling point of 77 degree Celsius ? Thx....
asked on June 20, 2016 
Math
Last semester, a certain professor gave 36 As out of 390 grades. If one of the professor's students from last semester were selected randomly, what is the probability that student received an A? (Assume that each student receives one grade.)
asked on March 12, 2013 
Physics
a 2 centimeter diameter ball of 50 grams rolls at constant velocity across a table. it takes 4 seconds to travel 3 meters. Sketch graph of horizontal position, velocity and acceleration.
asked on December 5, 2012 
ACCT
The question is: In the journal provided, prepare year end adjustments for the following situations. Omit explanations. a. accrued interest on notes receivable is $105 b. of the $12,000 received in advance of earning a service, one third was still
asked on March 1, 2012 
english
how to write instructions for turning someone into a toad
asked on June 27, 2009 
math
Write a quadractic equation having given equations? 9,9i
asked on November 15, 2012 
Ap World
what does colonial legacy mean?
asked on April 26, 2012 
probability
1. The time it takes a student to cycle to school is normally distributed with a mean of 15 minutes and a variance of 2. The student has to be at school at 8.00a.m. At what time should the student leave her house so that she will be late only 4% of the
asked on April 10, 2011 
geometry (high school)
if there are two tangent circles that have two external tangent lines that intersect at a 60 degree angle, what is the ratio of the radii.
asked on February 27, 2011 
Geometry
Hi, I have to use algebra to find the coordinates of the point where two lines intersect, the first line passes through the points 4,3 and 10,0 and the second line is y=6. Any ideas would be very much appreciated, many thanks
asked on July 14, 2010 
math
When two digits of thbase 10 representation of an inteer are intercharged, the diference bewen the old number and the new number is divisible by 9. Why? What happens in other bases? 10A + B  10B A= difference. This reduces to 9A  9B 9(Ab)= difference.
asked on January 20, 2007 
Physics
The driver of a sport car pushed down the accelerator so that the engine pushes the care forward with a force of 2500N,s tarting from rest. How fast the car can go after 20s later? I have tried this by using v=u+at but i don't have a. From F=ma, i cant get
asked on August 28, 2016 
MATH
You would like to construct a 400squarefoot rectangular garden along your driveway. The fencing on the driveway side costs $15 per linear foot, while the fencing for the other three sides costs $8 per linear foot. Write an expression for the cost of the
asked on October 10, 2015 
english
Would Culture, Heroism, and Supernatural Forces in Beowulf be a good topic for an expository essay on Beowulf being an epic poem?
asked on December 5, 2011 
Chemistry
An unknown mass of caco3 was added to an excess of 2mol/dm3 hcl. Calculate the total volume of co2 evolved.
asked on December 4, 2015 
math
Consider that the age, x, of a unicorn in human equivalent years can be given by the formula f(x) =  0.001618x4 + 0.057326x3 – 1.1367x2 + 11.46x + 2.914. When a unicorn is 2.5 years old, what is its age in human equivalent years? What about when it is
asked on July 17, 2011 
Algebra
Could someone tell me the solution for x^2  3x = 0, i know x = 3 but I just need to know how to get there please
asked on May 16, 2010 
physics
what would be the significance of the photoelectric effect graph if it a) passed through the origin b) had a positive y intercept
asked on April 28, 2010 
Math
Juana paid $1,200 for a sofa. The price of the sofa Ben purchased was 3/5 the price that Juana paid. How much did Ben pay for his sofa?
asked on October 20, 2016 
math
WHAT ARE THE QUESTION IN BUSMATH?
asked on August 3, 2015 
Math/modelling
Hi, I have a linear model with equation p =5.1t  28, which concerns breeding pairs of birds where p is the number of breeding pairs and t is the year. I need to use this model to estimate the number of breeding pairs in year 15. I would assume to do this
asked on July 13, 2010

math
0.45
posted on June 27, 2016 
Physics
2.3i+4.5j
posted on March 11, 2016 
MATH
Thank you Steve :)
posted on October 11, 2015 
calculus
i don't understand this part:dt/(t^2 + 1) = (1/2)ln(t^2 + 1)
posted on March 19, 2013 
Math homework
when given 5,5,5,5,5 using the order of operations and parenthesesto make a true expression where would i place my ,+ *,/ to make the answer equal 1
posted on September 28, 2010