This document contains an engineering economics homework assignment from Zarqa University. It includes 14 questions about time value of money concepts like simple vs. compound interest, calculating rates of return, and using the rule of 72. The questions cover cash flows, loans, certificates of deposit, and investment growth over various time periods at given interest rates. Students are asked to define terms, calculate amounts, draw cash flow diagrams, and estimate doubling/quadrupling times using the rule of 72.