I think the answer is b
I hope this helps :)
Answer:

Step-by-step explanation:
From the question we are told that
Architect Measures 2.5 feet (using the Brussels measurement)
Generally in Brussels 
Therefore

Generally in Aalst 
Therefore Mathematically converting to feet in Aalst measurement we get
-0.0375
-1/2
———- ( 7 1/2 ) =-3/80
100
I got 36000000 . Hope this helps