25.3 feet per second
Step-by-step explanation:
First, let's find how much did she go down in those 3 seconds.
266-190=76
Now, let's divide 76 by 3 to find how much did she go down in 1 second
76/3=25 R1
Now, let's change 25 R1 to a Fraction.
25 remainder 1 to fraction will be 25
Now, let's find the decimal answer
Now, let's round our answer to the nearest tenth
25.33
so, 3 is closest to 0 not to 10
So hence, our answer is 25.3
So, the submarines elevation was changing at a rate of 25.3 feet per second
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