Answer:
1) -95.
2) 15.
3) The conference center is on floor 5.
Step-by-step explanation:
1) Evaluating gives
2) Substituting gives
3) After going 4 floors down, we are on level -4. After going 9 floors up to the desired room, we are on level -4+9=5. So the conference center is on floor 5.