Which material is not a metamorphic rock a - obsidian b - marble c - slate d- gneiss answer asap

Becquerel expected to find ( he developed the photographic plate that had sun-exposed minerals on top of it. becquerel expected to find ( he developed the photographic plate that had been in the closed drawer.

The diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.