(order(?order) 
^ swrlb:greaterThan(D-variable(packageWeight) 50)) 
=> swrlb:equal(D-variable(packageWeight), 50)

(order(?order) 
^ hasItemContirmation(?order, ?itemConfirmationNo) 
^ swrlb:lessThanOrEqual(?orderDay, 30))
=> tracking(?itemConfirmationNo, false)

(order(?order)
^hasItemConfirmation(?order, ?itemConfrimationNo)
^hasAccount(?customer, ?account)
^delivery(?package, null))
=> charge(?account, nil)