Answer is Option C Lumen.It is also known as luminous energy.
Stronger.....................becasue gravitational force is force pulling all matter (anything that has mass and occupies space) . The more the matter (which also includes mass), the more the gravitational force.
<span>So, the answer is stronger. </span>
<span>Grasslands making up half of the African continent</span>
<span>17,179,8691,840</span> should be the correct answer
hope this helps
