Neco 2023 Commerce Question 35

In a company, a memo is sent from the head office to three regional offices via the email system. Each email experiences a transmission delay of 2 seconds and a processing delay of 5 seconds at the recipient before it can be read. After reading the memo, each regional manager forwards it to four branch managers, using the same system with the same delays. Once a branch manager reads the memo, he immediately sends an acknowledgment back to his regional manager, which again incurs the same transmission and processing delays, and the regional manager forwards the acknowledgment to the head office with the same delays. Calculate the total time, in seconds, from the moment the head office sends the original memo until the head office receives all acknowledgments.