Why are autotrophs called the producers in an ecosystem .?

Two critical interventions to turn around the opioid crises are:

What substance is the most acidic. lemon juice. tomato juice. sodium hydroxide. water

Which action is a reflex action. a. asking for coffe in a cold climate b. blinking when light is flashed in the eyes c. drinking water when thirsty. d. swallowing food e. taking an exam