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April 16, 2014

April 16, 2014

Posted by **jessica** on Tuesday, March 6, 2012 at 11:03pm.

a) Determine the function A’, which represent the rate of decay of the substance.

b) what is the half-life for this substance?

c) what is the rate of decay when half the substance has decayed?

- Science -
**drwls**, Tuesday, March 6, 2012 at 11:20pma) A' = dA/dt = -100*(1.6^-t)*ln1.6

= -47*1.6^-t

b) When A(t) = (1/2)A(0),

100*1.6^-t = 50

1.6^-t = 0.5

-t ln1.6 = ln0.5

t = 1.475

c) A' at t = 1.475 is half the rate at t = 0, or -23.5

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