Question 118049
The revenue (R) for a sandwich shop is directly proportional to its advertising budget (B).  
So, {{{R = kB}}}.
When B = 2000, R = 120000, so {{{k = R/B = 120000/2000 = 60}}}.
So when R = 180000, {{{B = R/k = 180000/60 = 3000}}}.

Hence, the owner spend $3000 on advertising.