Answer:
I think the right answer is option B.
Answer:

Explanation:
Given that,
Frequency of a radio antenna is 1 MHz
Power, P = 21 kW
We need to find the the waves intensity 25 km from the antenna
. The object emits intenisty evenly in all direction. It can be given by :

So, the wave intensity 25 km from the antenna is
.
B. Please mark me the brilliantest pls
Thermonuclear fusion is when matter is heated to a high degree