78. Determine the number of significant figures in the following measurements: (a) 0.0009, (b) 15,450.0, (C)
6x103, (d) 87.990, and (e) 30.42,
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Which describe reflection? check all that apply. light bounces off a boundary.

What event happens once every month

Once a sound recording is made, how is the sound reproduced? by converting passive sound waves into active sound waves by converting sound waves into electronic signals by converting the electronic signals back into sound waves by speeding up the stored sound waves