List four common ions with a valence electron configuration of [Kr]. List the ions in the order of increasing atomic number. Hint: two anions and two cations.

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

Stage in which a typical star has completely stopped fusion

Which of the following represents the ester functional group? a. -coo- b. -cho c. -cooh d. c=o