Q: at the same time, the subject matter ... is chosen so that ... all the most generally useful fundamental ideas of the science of waves in fluids can be developed at length, one after another.

A: At the same time, the subject matter ... is chosen so that ... all the most generally useful fundamental ideas of the science of waves in fluids can be developed at length, one after another.
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Q: 4:7 and when they had set them in the midst, they asked, by what power, or by what name, have ye done this?

A: 4:7 And when they had set them in the midst, they asked, By what power, or by what name, have ye done this?
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Q: how quickly depends on the technological development.

A:
How quickly depends on the technological development.
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