Question

three students measured the height of a lab table each using a different meter stick. One student reported a height of 98cm, another reported a height of 70 cm. The most likely explanation for the difference in the reported heights is that one

Answer 1

The difference between the two students that we know of is that they used a different meter stick. So the difference would be best attributed to  the different tools they used.

Note, this is quite a huge difference. It's likely that one of the sticks, or both, are quite defect.