Most likely the students are using a crude measurement of time, like a stopwatch. They would get the best results with a scientific apparatus that uses a computer and optical sensors. Even recording their dropped objects with a video camera and analyzing the video would give more consistent results. Results will also vary greatly if different people are taking the time measures instead of one person making all measurements.
Only animals in the same <u>species</u> can always breed and have fertile offspring.
Although animals in the same genus<em> can </em>breed, their offspring are usually infertile.
The common characteristic of those two organisms is hard spherical shells (exoskeleton).
Foraminiferans are single cell marine eukaryotes divided into granular endoplasm and transparent ectoplasm. Foraminiferans are enveloped with tests, hard shells, usually composed of calcium carbonate (sometimes from organic compounds or silica).
Coccolithophore is a unicellular, eukaryotic alga with special calcium carbonate plates (or scales) of uncertain function (coccoliths). Each unicellular alga is enclosed in its own collection of coccoliths, the which make up its exoskeleton- coccosphere.
A.<span>Beneficial insects may be adversely affected. </span>