Hello!
The answer is:
-D. Communication with friends and family after other systems were disabled by a major earthquake.
I hope this helps you! :)
Explanation:
In engineering, system integration is process of bringing various component subsystems together into one single system and also ensuring that these subsystems function as one system together.
In information technology, it is process of linking together various computing systems and various software applications functionally or physically, to act as coordinated whole.
System integrator integrates various discrete systems utilizing variety of techniques.
Answer:
a.about 3 or 4 miles per hour
