$10\mathrm{.}5$ Consider the model with a single regressor. This model also can be written as

$Y_{it}={}_0+{}_1{x}_{1,it}+{}_{2}B{2}_t+$cdots$+{}_{T}B{T}_t+{}_{2}D{2}_i+$cdots$+{}_{n}D{n}_i+u_{it},$

where $B{2}_t=1$ if $t=2$ and $0$ otherwise, $D{2}_i=1$ if $i=2$ and $0$ otherwise, and so forth How are the coefficients $({}_0,{}_2,$dots,${}_T,{}_2,$dots,${}_n)$ related to the coefficients $({}_1,$dots,${}_n,{}_1,$dots,${}_T)?$