Delta metal is an alloy of__________________?

A. 94% aluminium, 4% copper and 0.5% Mn, Mg, Si and Fe
B. 92.5% aluminium, 40% copper, 2% nickel, and 1.5% Mg
C. 10% aluminium and 90% copper
D. 90% magnesium and 9% aluminium with some copper
E. 94% aluminium and 6% tin

A. silver and some impurities
B. refined silver
C. nickel, copper and zinc
D. nickel and copper
E. silver and gold

A. has a fixed structure under all conditions
B. exists in several crystal forms at different temperatures
C. responds to heat treatment
D. has its atoms distributed in a random pattern
E. none of the above

A. F.C.C.
B. B.C.C.
C. H.C.P.
D. Orthorhombic crystalline structure
E. none of the above

A. 0.1%
B. 0.2%
C. 0.4%
D. 0.6%
E. 0.8%