Answer:
b. it is weak because it does not provide details about Harriet Tubman's life.
Explanation:
I think that's pretty self explanatory.
The electromagnetic wave is self propagating, what I mean by that is, an electric field generates a magnetic field at 90 degree phase angle, and the magnetic wave you get as a result generates the electric wave at the same phase angle. The interchange of electric to magnetic and vice versa continues and lets the electromagnetic waves to travel without any medium. Quite interesting, really!
It would be C because most of the time humans dont change the landscape.
All of the above. However C is most relevant.
