World Geography
The length of the tropical years (the time interval between successive occurrences of the spring equinox) is decreasing very slowly as a result of
small, progressive change in earth's orbit around the sun
both (a) and (b)
small, progressive changes in the earth's rotational speed
Salinity is directly positively related to seawater density.On an average, seawater density increases with increasing salinity and vice versa.E.g. Density of pure water is 1.00 g/cm3 and density of water with 35% salinity is 1.028 g/cm3.