Answer: 
Antonio is at -24 meters where ocean floor is at -94 meter So from the ocean floor he is 94 – 24 = 70 meter above. 
Solution: 
Given that ocean floor is at -94 meter. 
Antonio has reached -12 meters. He is continuously moving down. 
Number of meters he moves down in one minute = -4m 
Number of meters he moves down in 3 minutes = Number of meters he moves down in one minute 
 3
 3
Number of meters he moves down in 3 minutes = 
 = -12 meters.
 = -12 meters. 
After here minutes Antonio reached to -12 + -12 = -24 meters. 
So Antonio is at -24 meters where ocean floor is at -94 meter .So from the ocean floor he is 94 – 24 = 70 meter above