Predict the period, group number and block of the following elements. `A`(at.no`1=8`), `B` (at.no.
Channel: Doubtnut
Date: 2020-07-26

Predict the period, group number and block of the following elements. `A`(at.no`1=8`), `B` (at.no. `= 11`), `C` (at.no. `= 28`), `D` (at.no. `= 54`).