An automated hydroponic greenhouse uses an algorithm to determine the volume of concentrated liquid nutrient (in ml) to dispense into a water tank. This calculation is based on the current water acidity level, phLevel, and the growth stage code of the crops, stageCode.

Figure 1

phLevel ← USERINPUT
stageCode ← USERINPUT
nutrientVolume ← 0.0
alertLow ← "Acidity level critical"
alertStage ← "Invalid growth stage"
IF stageCode ≤ 4 AND phLevel > 4.0 THEN
    IF phLevel > 6.5 THEN
        nutrientVolume ← 5.0
        OUTPUT nutrientVolume
    ELSE IF phLevel > 5.2 THEN
        nutrientVolume ← (phLevel * 8.0) - 20.0
        OUTPUT nutrientVolume
    ELSE
        OUTPUT alertLow
    ENDIF
ELSE
    OUTPUT alertStage
ENDIF

Using Figure 1, complete the table below.