1. Under UL 48, which of the following qualifies as a Class 2 circuit? 1.根据 UL 48，以下哪一种符合 Class 2（2 类）电路的定义？

A. A circuit supplied by a transformer power supply or battery at any voltage rating A. 由变压器、电源或电池供电，且具有任意额定电压的电路

B. A circuit supplied by a transformer power supply or battery with an open-circuit voltage not exceeding 30 VAC or 60 VDC B. 由变压器、电源或电池供电，开路电压不超过 30 VAC 或 60 VDC 的电路

C. A circuit supplied by a transformer power supply or battery with an open-circuit voltage not exceeding 120 VAC or 240 VDC C. 由变压器、电源或电池供电，开路电压不超过 120 VAC 或 240 VDC 的电路

D. A circuit specifically intended for electric signs and rated below 600 volts D. 专门用于电气招牌且额定电压低于 600 V 的电路

2.Which metal-halide lamp is NOT permitted under the Alternative Lighting Sources compliance option for electrical signs? 2.以下哪一种金属卤化物灯（Metal-Halide Lamp）不允许在电气招牌的 Alternative Lighting Sources（替代照明光源）合规选项下使用？

A. 250-watt lamp A. 250 瓦灯

B. 320-watt lamp B. 320 瓦灯

C. 200-watt lamp C. 200 瓦灯

D. 150-watt lamp D. 150 瓦灯

3.Who is legally authorized to prepare engineering calculations for an electrical sign? 3.谁在法律上有资格为电气招牌编制工程计算？

A. Civil engineer A. 土木工程师

B. General Engineering contractor B. 通用工程承包商

C. Mechanical engineer C. 机械工程师

D. Electrical sign contractor D. 电气招牌承包商

4.Marquee signs are most commonly installed at which types of establishments? 4.Marquee 招牌（大门楣招牌）最常安装在哪些类型的场所？

A. Retail shops and cabins A. 零售商店和小屋

B. Roads and railway stations B. 道路和火车站

C. Highways and freeways C. 高速公路和快速道路

D. Restaurants and theaters D. 餐厅和电影院

5.Projection signs and swing signs are generally classified under which category? 5.投射式招牌（Projection Signs）和悬摆式招牌（Swing Signs）通常归类为哪一种？

A. Indoor signs A. 室内招牌

B. Outdoor signs B. 户外招牌

C. Commercial signs C. 商业招牌

D. Standard signs D. 标准招牌

6.Under the same environmental conditions, what is the relationship between the visibility distances of red and green neon illumination? 6.在相同的环境条件下，红色和绿色霓虹灯照明的可见距离有什么关系？

A. Both colors have the same visibility distance A. 两种颜色具有相同的可见距离

B. Red neon has approximately 35% greater visibility distance than green neon B. 红色霓虹灯的可见距离约比绿色霓虹灯长 35%

C. Green neon has approximately 35% greater visibility distance than red neon C. 绿色霓虹灯的可见距离约比红色霓虹灯长 35%

D. No recognized relationship exists D. 两者之间不存在公认的关系

7.If a letter formed from red neon tubing is 10 feet high, what is its maximum approximate visibility distance? 7.如果由红色霓虹灯管制成的字母高度为 10 英尺，其最大大约可见距离是多少？

A. 4000 feet A. 4000 英尺

B. 4500 feet B. 4500 英尺

C. 5000 feet C. 5000 英尺

D. 6000 feet D. 6000 英尺

8.Which statement correctly describes the penetration of neon tube illumination under rainy conditions? 8.以下哪项正确描述下雨条件下霓虹灯照明的穿透能力？

A. Neon illumination is 20% less penetrating in rain than in clear weather A. 雨天的霓虹灯照明穿透能力比晴天低 20%

B. Neon illumination is 20% more penetrating in clear weather than in rain B. 晴天的霓虹灯照明穿透能力比雨天高 20%

C. Neon illumination is 20% more penetrating in rain than in clear weather C. 雨天的霓虹灯照明穿透能力比晴天高 20%

D. None of the above D. 以上都不正确

9.In the red-light range, what is the commonly recognized efficiency relationship between a Mazda lamp and a neon tube in the sign industry? 9.在红光范围内，招牌行业通常认为 Mazda 灯与霓虹灯管之间的效率关系是什么？

A. A Mazda lamp is approximately five times more efficient than a neon tube A. Mazda 灯的效率约是霓虹灯管的 5 倍

B. A Mazda lamp is approximately five times less efficient than a neon tube B. Mazda 灯的效率约是霓虹灯管的 1/5

C. Both provide approximately the same lighting efficiency C. 两者的照明效率大致相同

D. No established efficiency relationship exists D. 两者之间没有确定的效率关系

10.At approximately what wavelength does neon produce its maximum light output under rainy-weather conditions? 10.在雨天条件下，霓虹灯产生最大光输出的大约波长是多少？

A. 435 millimicrons A. 435 毫微米

B. 535 millimicrons B. 535 毫微米

C. 635 millimicrons C. 635 毫微米

D. 735 millimicrons D. 735 毫微米

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