Why are the planets closest to the sun composed of mostly rock while those further away are composed mostly of gas and ice?

What is the polyatamic ion of thiosulfate

Which ocean zone has the most abundant primary producer and why a) the abyssopelagic zone ,du to the absence of light and cold water temperatureb) the bathypelagic zone, due to the absence of light and cold water temperaturec) the mesopelagic zone ,due to uts high light availability and warm water temperature d) the epipelagic zone, due to its high light availability and warm water temperature

Which type of fossil does this image depict?