A、Tank. B、Helicopter. C、Remote control unit. D、Laser light. B

The latest report by an independent investigative panel of experts confirms that the Assad regime is responsible for a third chemical weapons attack on the Syrian people.
In its October 2016 report, the Organization for the Prohibition of Chemical Weapons—United Nations Joint Investigative Mechanism, or JIM, concluded the Syrian Arab Armed Forces used weaponized chlorine in the town of Qmenas in 2015. This latest finding followed an August 2016 report where the JIM concluded that (1)Syrian Arab Armed Forces used helicopters to drop barrel bombs filled with chlorine gas on the civilian population of Sarmin in 2015, and had attacked the town of Talmenes in a similar way in 2014. (2)That report additionally found that Da’esh used mustard gas in an attack in 2015 in Marea. The Leadership Panel of the JIM reaffirmed its belief that it is absolutely critical to hold those who use or intend to use chemicals as weapons accountable for their acts.
Questions 1 and 2 are based on the news report you have just heard.
1.What did Syrian Arab Armed Forces use to launch barrel bombs?
2.Which kind of chemical weapons was used in 2015 in Marea?