df <- data.frame(
id = c(10,11,12,13),
name = c('sai,ram,deepika,sahithi'),
gender = c('M','M','F','F'),

dob = as.Date(c('1990-10-02','1981-3-24','1987-6-14','1985-8-16')),
state = c('CA','NY',NA,NA),
row.names=c('r1','r2','r3','r4')
)
df