if Cameron Dives to a death of 40 ft and the water changes every 10 ft, what will the temperature be at the depth? write an equation to solve the problem. PLEASE HELPP

Ineed me i stuck and i don’t want to get it wrong

Will mark brainliest for correct answer! i have been on this problem for an hour and can't find the answer. i'm begging here! incase you cant read the instructions in the picture because of too much or too little lighting: note: enter your answer and show all the steps that you use to solve this problem in the space provided.write a list of steps that are needed to find the measure of b. provide all steps as clear as possible, !

Ineed to find the answer to number 2