Can someone answer this or explain it?

The x in the formula is the depth.

You are given two different depths, replace x with the depths, solve for T, then subtract the to find the difference:

At 1200 meters the temperature is:

T = 4500/1200 = 3.75 degrees

At 3750 meters the temperature is:

T = 4500 / 3750 = 1.20 degrees.

The difference in temperature between the two depths is:

3.75 - 1.20 = 2.55 degrees C.

1/3+2/7  

=7/21+6/21  

=13/21

Step-by-step explanation: