Question

the lab procedure involves two trays of plants. select all factors below that are the same (constant) for both trays. the remaining factors are the variables of the lab procedure. amount of water given to the plants growth of the plants presence of worms in the soil environment of the plants the amount of sunlight given done

Explanation:

In a controlled experiment (like a plant lab procedure), constants are factors kept the same to ensure a fair test, while variables are what's changed or measured. Growth of plants is the dependent variable (measured), so it's not a constant. The other factors (water, worms, environment, sunlight) are typically controlled (kept same) to isolate the variable being tested. Wait, no—wait, the question is which are the same (constant). Wait, actually, in a plant experiment, to have a valid test, we keep factors like water amount, presence of worms (if not the variable), environment (temp, humidity), and sunlight amount constant. Growth is the outcome (variable). So the constants here would be amount of water, presence of worms, environment, amount of sunlight. Wait, but let's re-express:

• Amount of water: kept same (constant) to not affect growth other than the tested variable.
• Growth of plants: this is what's measured (dependent variable), so it's not constant (it changes based on other factors), so not a constant.
• Presence of worms: if worms are not the variable, they're kept same (constant) to ensure soil conditions are same.
• Environment of the plants: temperature, humidity, etc., kept same (constant) for both trays.
• Amount of sunlight: kept same (constant) to ensure light is not a confounding factor.

So the factors that are the same (constant) are amount of water, presence of worms, environment, amount of sunlight. Wait, but the options are checkboxes. So the correct ones to select (as constant) are:

• amount of water given to the plants
• presence of worms in the soil
• environment of the plants
• the amount of sunlight given

Growth is not constant (it's the variable we measure), so we don't select that.

Answer:

The factors that are the same (constant) for both trays are:

• $\boldsymbol{\text{amount of water given to the plants}}$
• $\boldsymbol{\text{presence of worms in the soil}}$
• $\boldsymbol{\text{environment of the plants}}$
• $\boldsymbol{\text{the amount of sunlight given}}$

(These are selected as constants; "growth of the plants" is a variable, not a constant.)