From a container having pure milk, 35% is replaced by water and the process is repeated thrice. At the end of the third operation. the purity of the milk is:
1
\(21\frac{23}{80}\%\)
2
\(37\frac{21}{80}\%\)
3
\(23\frac{37}{80}\%\)
4
\(27\frac{37}{80}\%\)