Answer:
B) $50,000
Explanation:
Month     total sales         $ collected          outstanding credit
January    $40,000         $16,000                 $24,000
February   $60,000    $24,000 + $12,000          $12,000 + $36,000     Â
March     $50,000  $20,000 + $12,000 + $18,000   $18,000 + $30,000
during March, Eccleston should collect ($50,000 x 40% from current sales) + ($24,000 x 50% from January) + ($36,000 x 50% from February) = $20,000 + $12,000 + $18,000 = $50,000