Charcoal samples from Stonehenge in England emit 45.1% of the disintegrations per gram of carbon per minute expected for living tissue. What is the age of this charcoal? A. 3550 years
B. 6580 years
C. 4410 years
D. 9190 years
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Motivation cannot be developed with practice; a person either possesses it or they do not.

Iknow the answer is a but i don't know why

Butadiene undergoes a reaction at a certain temperature in the gas phase as follows: 2c4h6(g) --> c8h12(g) the following data were collected for this reaction: time (min) [c4h6] (m) 0 0.36 15 0.30 30 0.25 48 0.19 75 0. determine the order of the reaction and the rate constant. 1st order and k = 4.3x10 -4 s-1 1st order and k = 2.3x10-4 s-1 2nd order and k = 4.3x10-4 s-1 2nd order and k = 2.3x10-4 s-1 zero and k = 4.3x10-4 s-1