三道英文版的物理题,求翻译并解答!谢谢
1. A nurse counts 76 heartbeats in one minute. What are the period and frequency of the heart's oscillations?
2. New York's 300-m high Citicorp Tower oscillates in the wind with a period of 6.80s. Calculate its frequency of vibration.
3. Calculate the speed of waves in a puddle that are 0.15m apart and made by tapping the water surface twice each second.