The answer is D. 4 because its after perception
Answer: It was obtained 8515 years ago
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) to find the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.


b) for completion of 36% of reaction


t = 8515 years
The time was 8515 years.
Answer:
D. Hydroelectric
Explanation:
The given structure is of a dam where Hydroelectricity is produced.
Confused on what has to be answered but that’s the spirit
Answer:
xylem and phloem
Explanation:
Xylem and phloem are basically the blood vessels of plants because they transport substances.