Task: Question Answering
Input (English): Problem: a company has a hierarchical system where for every 10 workers , there is one team lead , and for every 3 teams leads , there is one supervisor . if the company has 13 supervisors , how many workers does it have ? 
Options: a ) 140 , b ) 321 , c ) 390 , d ) 500 , e ) 130
Output (English): c