Read this and answer the question. If the question is unanswerable, say "unanswerable".

The Royal Australian Navy is in the process of procuring two Canberra-class LHD's, the first of which was commissioned in November 2015, while the second is expected to enter service in 2016. The ships will be the largest in Australian naval history. Their primary roles are to embark, transport and deploy an embarked force and to carry out or support humanitarian assistance missions. The LHD is capable of launching multiple helicopters at one time while maintaining an amphibious capability of 1,000 troops and their supporting vehicles (tanks, armoured personnel carriers etc.). The Australian Defence Minister has publicly raised the possibility of procuring F-35B STOVL aircraft for the carrier, stating that it "has been on the table since day one and stating the LHD's are "STOVL capable".

How many tanks is the LHD capable of launching?
unanswerable