Some of the safety rules would include to tie one's hair if it is long and do roll up sleeves if needed. Another is always point the opening of the burner away from one's self and others when heating and lastly never to leave the burner unattended.
What must happen in order for a new species to evolve? They must mate with other species; the gene pools of two populations must become separated, or reproductively isolated.
The spear is 4620 years old.
N=N0e^-kt
N0 = initial amount of C-14 (at time t = 0)
N = amount of C-14 at time t
t = time, in years
k = 0.0001
N/N0 = e^-kt
we know N/N0 is 0.63
so we have:
0.63 = e^-kt
we can take the ln of both sides, leaving us with:
ln0.63 = -kt
t = ln0.63 / -(0.0001)
t = 4620 years
hope this helps with your thing!
-keynerd23
yes, his conclusion is supported by evidence from his experiment