Answer:
Total collectible in November = $826,560
Explanation.
Sirignano Corporation
October
Sales $84 x 8,400 = 705,600
Collections in Oct 40% = $282,240
November
Sales $84 x 12,000 = 1,008,000
Collections in Nov 40% = $403,200
60% Oct collections in Nov = $423,360
Total collectible in Nov = $826,560
Collections in Dec 60% = $604,800