世界上有袋类动物生存的大陆除_______ 大陆外，还有_______ 大陆。
澳大利亚；南美
_______ is believed, all the scientists subscribe to the view ______ the increase in the earth’s temperature is due to the burning of fossil fuels to produce energy.
A．It; \
B．As ; that
C．It; if
D．As; whether
铁的含碳量（）%。
A.小于2.11
B.大于2.11
C.1.8
D.1.2
