In order to achieve a bigger splash in their next trial, all the students need to do is use a ball with a larger circumference.
A dimensional object dropped into a liquid will always displace its own volume from the liquid.
For a basketball, the circumference is a function of its volume. In other words, the larger the circumference, the larger the volume.
This means that a basketball with a larger volume will displace more water from the pool than one with a lower volume.
Hence, to make a bigger splash, a basketball with a larger circumference would be needed.
More on displacement and volume can be found here: https://brainly.com/question/17322215