opal is a hydrated form of silica. if a laboratory analysis of a sample of opal reveals it to contain 29.2% si, 33.3% o, and 37.5% h_2o, what is its empirical formula?

Which of the following is an example of an opposing signal? no examplthates given.   i would say, that traffic lights in a city at major intersections direct the flow of traffic in opposite directions so would be an example.also, stop signs on either side of the same street would be an example. at a train crossing, the light for allowing car traffic in opposite directions or not would be another example.

No, mark me ! ((brainliest))

The answer should be d if i’m wrong i’ll change my answer and fix it for you