Calculate how much GDP would change as a result of each of the following transactions:

(a) The government purchases an airplane for $6 million.

(b) A citizen sells a used car for $6,000.

(c) A citizen sells a used car to a dealer for $6,000, who resells it to a consumer for $7,500.

(d) A citizen sells a bond for $1,000 that they bought last year for $600.

(e) The government issues a welfare cheque for $1,250 (ignore the administrative costs of issuing the check).