S$.$ Hopper purchased a new ride$-$on Jawnmower yesterday for $$750$ dollars at Home Depot. When he arrived home, he opened the box and realized that it needed to be assembled. He was unaware of that fact and pulled out his receipt which stated clearly, "Assembly Required." He called Home Depot and they sent out a young worker to assemble the lawn mower for $$100.$ The next day, $5.$ Hopper pulled the lawn mower out of his garage and when attempting to use it$,$ it would not start. Frustrated $($his lawn was growing at a rapid rate$)$ he screamed out, $"$I$\text{'}$d sell this mower for $$50!)$ S$.$ Hopper's neighbor Frank happened to be walking his Labradoodle in front of Hopper's home and immediately replied, "I'll take it$"$ and pulled a $$50$ bill from his pocket and brought it to $S.$ Hopper.

What are the three elements necessary to create an offer $?$ Was the statement made by S$.$ Hopper a valid offer $?$ Why or why not $?$ Will S$.$ Hopper be forced to sell the lawnmower to Frank? Respond to at least one other student's post in a meaningful way $.$