ElectricPavlov

But we are given the equation of how this particular substance decays, with k = (-1/29)     = -.03448     whay are you calculating ANOTHER  (different)  k ???

1.02857 x 10^(-1)   is one way....

engineers would say  102.857 x 10 ^(-3)

First, there is approximately 365 1/4 days in a year NOT 355 ....  so every FOUR years we have a LEAP DAY (Feb 29th)... that is a LITTLE off too, so every few years a LEAP SECOND is added to keep things accurate.

the days ARE 24 hours (defined as the rotation time of the earth around its axis)....only the YEAR (defined as the time of the earth's ORBIT around the sun)  has a 1/4 day longer than 365...i.e.  the DAYS aren't longer, the YEAR is.

but your question asks what .oo281491907  is.....    that is the fraction of an hour in your (sorry,...incorrect) calculations

.0028149 (3600) = 10 . 133 seconds/day

If you ignore wall friction , you will need TWO tubes that total the same AREA as the 5" tube

Area of 5" tube = pi r^2  = pi (2.5)^2 = 19.63 sq in

Two tubes, each would have to equal  19.63/2  sq in = 9.82 sq in

pi r^2 = 9.82    results in r =  1.768 inches.....   2 r = diameter = 3.54 inch diameter each

'i'  is DEFINED as the sqrt of (-1)      so example:    sqrt(-4)  = sqrt (4 x (-1) )  =  2 sqrt(-1) = 2 i

......and you misspelled   'were'       

If there WERE two chickens....it depends into how many PIECES you cut the chickens.

Not sure what you are doing on this problem Guest #2...if I substitute your answer of 96.34 into the equation I get

m(t) = 3.0666   which is NOT   1/10 of the original 85 at t=0.

I come up with 66.77 years like Omi67 did