use $x=0$

Question $4$

$x=0$ for odd no$.$ in the second last digit of student ID and $x=2$ for zero or even no$.$ in the second last digit of student ID$)$

A classroom has dimensions of $12\mathrm{.}8m(L)6\mathrm{.}4m(W)3m(H).$ The reflectances of the ceiling, the walls, and the floor are $0\mathrm{.}7,0\mathrm{.}5$ and $0\mathrm{.}2,$ respectively. The classroom is provided with an average of $350$ lux on a working plane which is $0\mathrm{.}7xm$ above the floor. The lighting installation contains a certain number of luminaires with the photometric data provided in Tables $3$ and $4.$ Each luminaire is suspended $0\mathrm{.}14m$ under the ceiling and houses two $30-W$ LED lamps with a luminous efficacy of $8xl\frac{m}{W}.$ The light output ratio of luminaires is $0\mathrm{.}7x.$ The total light loss factor is assumed to be $0\mathrm{.}85.$ The nominal spacing$-$to$-$height ratio is $1\mathrm{.}1.$

Table $3$ Utilization factor table

$\backslash$table$[[\backslash$table$[[$Reflectances:$],[$Ceiling$],[$Wall$],[$Floor cavity$]],\backslash$table$[[0\mathrm{.}70],[0\mathrm{.}50],[0\mathrm{.}20]],\backslash$table$[[0\mathrm{.}70],[0\mathrm{.}30],[0\mathrm{.}20]],\backslash$table$[[0\mathrm{.}50],[0\mathrm{.}50],[0\mathrm{.}20]],\backslash$table$[[0\mathrm{.}50],[0\mathrm{.}30],[0\mathrm{.}20]],\backslash$table$[[0\mathrm{.}30],[0\mathrm{.}30],[0\mathrm{.}20]]],[\backslash$table$[[$Room$],[$dimensions:$],[x$