A.Ag.
B.Zn.
C.Cu.
D.Au.

A.1,344.00
B.0,896.
C.2,240.00
D.0,448.

A.focusing
B.breaking
C.imposing
D.judging

A.didn’t he
B.don't they
C.did they
D.didn't they

A.has been upgraded
B.is upgraded
C.have been upgraded
D.has upgraded

A.on
B.in
C.from
D.with

A.the short the days become
B.the days become shorter
C.the shortest the days become
D.the shorter the days become

A.small round green
B.small green round
C.green small round
D.round small green

A.were writing
B.had written
C.wrote
D.was writing

A.due to
B.though
C.despite
D.because