When bending magnesium sheet, the recommended minimum internal bend radius in relation to material thickness is: 91 a) 3 to 6 X. b) 10 to 20 X. c) 20 to 30 X. d) 50 to 100 X. 8. The primary alloying element that makes steel stainless is: a) Chromium. b) Nickel. c) Manganese. d) Silicon. 9. For general workability, including forming and welding, the recommended stainless steel type is: a) 410. b) 430. c) 500 series. d) 304. 10. Titanium can remain metallurgically stable in temperatures up to: a) 5,000 degrees F. b) 1,000 degrees F. c) 500 degrees F. d) 250 degrees F. 11. The alloying elements that make up brass are: a) Copper and silicon. b) Lead and zinc. c) Copper and zinc. d) Tin and copper. 12. Electrolytic copper is a type that: a) Has a high annealing temperature. b) Work-hardens quickly. c) Does not work-harden easily. d) Contains a high percentage of phosphorus