Questions

Seawater or salt water is water from a sea or ocean.

On average, seawater in the world's oceans has a salinity of approximately 3.5% or 35 parts per thousand. This means that for every 1 litre (1000 mL) of seawater there are 35 grams of salts dissolved in it.

Hence, The average salinity of seawater is 3.5%.

It gets contaminated by lead

The name given to the bond between water molecules is a hydrogen bond. These bonds occur between the slightly negative oxygen of one water molecule and the slightly positive hydrogen of another water molecule. Hydrogen bonding gives water special physical properties.

The differences in electronegativity between hydrogen and oxygen lead to an unequal sharing of electrons. Electronegativity measures how strongly an atom attracts electrons. Oxygen, with its higher electronegativity, pulls on the shared electrons more, giving the oxygen atom a partial net negative charge. The shared electrons spend less time with the hydrogen atoms; therefore, the hydrogen regions of water have partial positive charges.

All the three statements lead to either increase in demand of goods and services or decrease in the supply. This leads to increase in general level of prices.

A tertiary consumer is an animal that obtains its nutrition by eating primary consumers and secondary consumers.

Usually tertiary consumers are carnivorous predators, although they may also be omnivores, which are animals that feed on both meat and plant material.

Tertiary consumers often occupy the top trophic level, and so are predated by no other animals; in this case they are called "apex predators". However, when they die their bodies will be consumed by scavengers and decomposers.