commandline session > dfrm print(dfrm dfrm > print(dfrm) V1 V2 1 Name Jeffrin 2 Age 35 3 Sex Male > dfrm print(dfrm) V1 1 Name-Jeffrin 2 Age-35 3 Sex-Male > dfrm print(dfrm) V1 1 Name-Jeffrin 2 Age-35 3 Sex-Male > class(dfrm$V1) [1] “factor” > class(dfrm$V1) [1] “factor” > class(dfrm$V2) [1] “NULL” > class(dfrm$V3) [1] “NULL” …