What is a property that can be observed without changing the substance into another substance.

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 change to the system wood cause the freely-moving piston to lower?

Which states of matter have particles that move independently of one another with very little attraction?