Answer:
64.5%
Step-by-step explanation:
Initial amount N° = ?
Remaining amount after decay = N = ?
k = decay constant = 0.00012 
t = time = 3650 year
fraction remaining will be N/N°
From the decay equation, N = N°
N/N° = 
N/N° = 
N/N° = 
N/N° = 0.645 = 64.5%
Answer: #7 is A and #8 is D
Step-by-step explanation:
Answer:
t=9
Step-by-step explanation:
subtract 9 from both sides
t/3=3
t=9
1 and 3 they share a relationship of +2, 3 and 6 share x2, 5 and 8 share +3, 7 and 21 share x3
Do what is in the parentheses then add