Also raking it in nearby were some guys who raked snow from rooftops. For the service, they charge as much as $500 an hour.
附近还有一些人在打扫屋顶上的雪，他们的费用是500美元一个小时。
A single, 3-hour charge of the Hanebrink's battery will get you a 100-mile riding range over concrete, sand, dirt or snow.
单次充3小时后的电池能够让你骑行100英里，包括混凝土、沙地、土地或雪地等多种地形。
Analogous to a snow avalanche on a steep mountain slope, an incoming light pulse initially frees just a few charge carriers which in turn free others until the original signal is amplified many times.
像陡峭山坡上的雪崩一样，一束入射光的脉冲最初仅仅释放少数的电荷载子(charge carrier)，这些电荷载子再轮流释放其他的载子，直到原始信号被放大很多次。
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