Question

1. measuring the length of a table using a ruler but accidentally starting from the wrong end. source of error: human error 2) in a plant growth experiment, a student tests different soil types, amounts of sunlight, and types of fertilizer all at once. source of error: too many independent variables 3) a student tests a new type of glue on only one piece of paper to see how strong it is. source of error: not enough trials 4) a student mixes up two beakers containing different solutions and labels them incorrectly. source of error:

Explanation:

1. Measuring from the wrong end of a ruler due to human action is a human - error.
2. Testing multiple variables (soil types, sunlight, fertilizer types) simultaneously makes it hard to determine which variable affects plant growth, a case of too many independent variables.
3. Testing a new glue on only one piece of paper lacks sufficient trials for reliable results.
4. Mixing up beakers and mis - labeling is a human - error in handling experimental materials.

Answer:

1. Human error
2. Too many independent variables
3. Not enough trials
4. Human error