Guide tubes are used to: (Multiple Choice) Question 26 options: a) assist in pushing the welding wire through the gun. b) direct the wire into the drive rolls, and into the gun liner. c) transfer gas to the welding gun. d) help apply pressure to the guide rollers. Question 27 (1 point) Listen U-shaped drive rolls are commonly used for: (Multiple Choice) Question 27 options: a) self-shielding welding wire only. b) larger diameter electrodes to provide more positive feeding. c) soft wires, such as aluminum, to prevent "crushing" the electrode. d) small diameter solid and tubular electrodes. Question 28 (1 point) Listen A manifold system is used when: (Multiple Choice) Question 28 options: a) stations using argon mixed gases only. b) there is only one welding station c) there are many welding stations using the same type of shielding gas. d) there are many welding stations using different types of shielding gases. Question 29 (1 point) Listen The gas regulator: (Multiple Choice) Question 29 options: a) reduces the pressure from the gas supply. b) must be fixed horizontally. c) can be used for any type of welding gas. d) is used to start and stop the gas flow to the welding gun. Question 30 (1 point) Listen The flowmeter: (Multiple Choice) Question 30 options: a) reduces the pressure from the gas supply and maintains a constant delivery pressure. b) can be used for any type of welding gas. c) is used to set the gas flow rate to the welding gun. d) is u