Questions $45-54$ are based on the following.

Urban Medical Clinics operates four for$-$profit, on$-$demand medical facilities in the suburbs of a large American city. For the past quarter, the financial results are as follows.

$\backslash$table$[[,\backslash$table$[[$North Center$],[$Clinic$]],\backslash$table$[[$East Center$],[$Clinic$]],\backslash$table$[[$West Center$],[$Clinic$]],\backslash$table$[[$South Center$],[$Clinic$]]],[$Service Revenue,$$320,000,$$$280,000,$$$410,000,$$$488,000$