Its b during how ever you say that word if not that then c not all the way sure tho
Half life is the time taken by a radioactive isotope to decay by half of its original mass. In this case the half life of carbon-14 is 5500 years.
The original mass is 30 g and the new mass is 3.75 g.
New mass = Original mass × (1/2)^n, where n is the number of half lives;
3.75 = 30 × (1/2)^n
1/8 = (1/2)^n
n = 3
Thus, the time taken will be; 3 × 5500 = 16500 years.
Answer:
See the answer below
Explanation:
<em>Amphibians are not totally adapted to live on land because the aquatic environment is needed for several life processes such as </em><em>reproduction</em><em>, </em><em>respiration</em><em>, and sometimes, </em><em>feeding</em><em>.</em>
<u>The eggs of amphibians are without any protective shells and will suffer desiccation in the terrestrial environment. Hence, water is needed in order to protect the eggs. In addition, the male am</u>phibians shed their sperm in the water close to the female eggs.
<u>The young ones of amphibians are essentially aquatic and may not survive out of water for a long time because they only breathe gills</u> - the lung is yet to develop or poorly developed at this stage. They have to grow and develop to a certain stage in water before they can start surviving on land.
The answers you need are:
D
E
C
A
B
