So, if we start instead with talking about the energy levels, we can relate these to frequency, because we already said that frequency is related to, or it's equal to the initial energy level here minus the final energy level there over Planck's constant to get us to frequency.

如果我们从讨论能级开始，我们可以联系到频率上,因为我们说过频率和能量相关,或者说等于初始能量,减去末态能量除以普朗克常数。

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But more than just an appropriate level of fisticuffs, the difficulty level remains constant throughout, rather than ramping up as you go, and meant that he could keep up with his older siblings without the usual headaches of needing my help every five seconds.

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"There's just a constant level of demand, " he said of the city.

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These positive effects are transitory, however, when local economies have insufficient permanent employment to justify a constant level of demand for new housing stock.

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