Comparative and experimental investigations are two of three scientific investigations, the other is descriptive investigations.
--hope this helps--
The simplest answer is that water is polar, while lipids are nonpolar.
Hand held visual distress signal flares is part of a vessel's safety equipment. It is used to summon help during danger and it should only be displayed when immediate or potential danger exist. It is very effective when party that can possibly help are reasonably nearby.
