I've been stuck on this question for two weeks, : ,)
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what causes a disturbance that results in a wave?
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i've written about 30 different answers, and they're all : ( it's only one (mabe two) word(s) and refers to waves in general, not just waves in water. like, for instance, electromagnetic waves, or sound waves.

How can one distinguish breccia from conglomerate? a. breccia contains angular clasts and conglomerate contains rounded clasts. b. breccia contains rounded clasts and conglomerate contains angular clasts. c. different minerals cement breccia than cement conglomerate. d. breccia contains sand and conglomerate contains silt.

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

Photoelectrons with a maximum speed of 6.50 x 107 m/s are ejected from a surface in the presence of light with a frequency of 6.75 x 1014hz. if the mass of an electron is 9.10 x 10-31 kg, calculate in joules the maximum kinetic energy of a single electron. 3.84 x 10-15 j 1.92 x 10-15 j 5.92 x 10-23 j 3.07 x 10-16 j