C. seems like the best answer. i may be wrong so don’t quote me on that
Answer:Science is the body of knowledge that explores the physical and natural world. Engineering is the application of knowledge in order to design, build and maintain a product or a process
Explanation:
Answer:

Explanation:
Cold water in: 
Hot water in: 

Step 1: Determine the rate of heat transfer in the heat exchanger




Step 2: Determine outlet temperature of hot water



Step 3: Determine the Logarithmic Mean Temperature Difference (LMTD)










Step 4: Determine required surface area of heat exchanger



Step 5: Determine length of heat exchanger



The answer would be 23 because the engines in a horse is a amount of 9 engines in 69 cars