One pair of students fills cup A to the rim and fills cup B only halfway. Which instruction have they failed to follow?
Read a Short Informational Passage · ELPAC Grades 6–8 reading. The correct answer, and the reasoning behind it.
A brief factual text — a notice, a label, a set of instructions — followed by questions.
Read the instructions. Then answer the question.
Lab Procedure: Testing Soil Drainage
Work in pairs. Label three clear cups A, B and C, and punch four holes of equal size in the bottom of each. Fill cup A with sand, cup B with potting soil and cup C with clay, using the same volume of material in every cup. Hold each cup over the collection jar and pour in exactly 100 milliliters of water. Start the timer the moment the water touches the surface, and stop it when the dripping stops. Record both the time and the volume collected. Do not press the material down, because packing it changes how quickly water moves through.
The question
Choose the best answer.
One pair of students fills cup A to the rim and fills cup B only halfway. Which instruction have they failed to follow?
- Punch four holes of equal size in the bottom of each cup.
- Use the same volume of material in every cup.Correct answer
- Pour in exactly 100 milliliters of water.
- Start the timer the moment the water touches the surface.
Why “Use the same volume of material in every cup.” is correct
Lab instructions at this level are written so that each step keeps one condition constant, and this question checks whether a student can tell which condition an error breaks. Unequal amounts of sand and soil break the instruction to use the same volume of material in every cup, which is what makes the drainage times comparable. The other three instructions are real steps in the procedure but are untouched by this particular mistake.
Why the other answers are wrong
- Punch four holes of equal size in the bottom of each cup. — The holes control how water leaves the cup; filling the cups unevenly does not change the holes.
- Pour in exactly 100 milliliters of water. — The water volume is measured separately and is still 100 milliliters for each cup.
- Start the timer the moment the water touches the surface. — When the timer starts is about the pair's technique, not about how much material is in the cups.
Practice more of this
More reading practice for Grades 6–8, or see the ELPAC practice test for grades 6–8. For other grades, see free ELPAC practice tests by grade.
This is an independent study resource. It is not affiliated with, endorsed by, or connected to the California Department of Education or the official ELPAC program. All questions here are original practice material written to match the published task formats.