Answer:
ASSET   ORIGINAL BASIS   RATE   PROPORTION   DEPRECIATION
Furniture     $60,000              8.93%         50%                           $2679
Machinery   $72,000              10.93%       12.5%                         $983.70
Truck           $20,000              19.20%         50%                         $1920
Machinery  $280,000             7.55%        62.5%                      $48,212.50
Computer    $80,000                                  50%                    <u>         -           </u>
TOTAL                                                                                    <u>   $53,795.20</u>
Explanation:
Based on the MARCS depreciation table rates:
For a 7-year recovery period under the Half-Year (HY) Convention, in the 5th year rate = 8.93%
For a 7-year recovery period under the Mid-Quarter (MQ) Convention, purchased during the first quarter, in the 4th year rate = 10.93%
For a 5-year recovery period under the Half-Year (HY) Convention, in the 3rd year rate = 19.20%
For a 7-year recovery period under the Mid-Quarter (MQ) Convention, purchased during the fourth quarter, in the 2nd year rate = 27.55%
For disposal during a year, 
Under the Half-year convention. The depreciation amount would be half i.e 50% of the total depreciation for the year
Under the Mid-quarter convention the percentage applied to the full year disposal is
12.5% for First Quarter
37.5% for Second Quarter
62.5% for Third Quarter
87.5% for Fourth Quarter