Answer:
$8,800 
Step-by-step explanation:
As per the data given in the question, 
 We can calculate the amount of Purchasing department expense to be allocated to Assembly by using following formula:
Purchasing department expense to be allocated to Assembly = Total cost for purchasing department × no. of purchasing order ÷ total no. of purchasing orders in all departments 
= $44,000 × 4 ÷ 20 
= $8,800 
We simply applied the above formula to compute the amount of purchasing department expense.