# 2Multiple ChoiceWhich organ in the human body is responsible for pumping blood?LiverBrainHeartLungs
# 3Multiple ChoiceWhat is the process called when plants make their own food using sunlight?PhotosynthesisRespirationDigestionEvaporation
# 5Multiple ChoiceWhat is the main gas found in the Earth's atmosphere?OxygenNitrogenCarbon DioxideHydrogen
# 7Multiple ChoiceWhich ocean is the largest by surface area?Atlantic OceanIndian OceanArctic OceanPacific Ocean