The answer to the first question above is letter A. A deputy is the support position for all of the following positions, EXCEPT the Incident Commander.
The answer to the second question above is letter A. The role description of the Liaison Officer is the point of contact for other response organizations.
B Collaspse of Soviet Union cause Chernobyl happened in the middle of the Cold War
Do you need the answer from the quadratic formula? if so:

x^2=a
-3x=b
-18=c






Your answer would then be 6 and -3