Ice floats<span> on water </span>because<span> hydrogen bonding makes liquid water unusually dense</span>
In one of the studies of about rats in Easter Island, it was believed that rats were the reason for the decrease of palm trees.
According to a system framework study, there are relationships between the birth and death of people with the rats and the palm trees. It explains that peoples' population in Easter island has a relationship with rats and palm trees in the area.
<span>The number of palm trees decreases because of the increased number of rats that eats its fruits. Seed germination became frequently interfered because of this activity.
</span><span>However, the slow growth of palm trees was also blamed for the tree cutting off the people.</span>
All structures and their functions have cells
The energy produced from flow of water or "Hydro-power" is different to energy produced from iron, petroleum and coal as it is a clean and renewable form of energy. Hydro-power is derived from the kinetic energy of the natural flow of water like in the case of a water mill whereas the other forms listed require combustion of the fuel source that produces harmful gases leaving a negative impact on the environment. Also, hydro-power is one of the cheapest forms of energy production.
However, it should be noted that large-scale production of electrical energy from flowing water known as "Hydroelectric Power" uses man-made dams to store water in lakes as a source of potential energy. These dams can also have a negative impact on the environment as the natural flow of water is restricted. Some scientists also suggest that the construction of a dam leads to an increase in the number of earthquakes in and around the area of construction.