Fill up the blanks:

(a) The method of separating seeds of paddy from its stalks is called ____.

(b) When milk, cooled after boiling, is poured onto a piece of cloth the cream (malai) is left behind on it. This process of separating cream from milk is an example of ____.

(c) Salt is obtained from seawater by the process of _____.

(d) Impurities settled at the bottom when muddy water was kept overnight in in a bucket. The clear water was then poured off from the top. The process of separation used in this example is called ____.