c$.$ In the dataset that contains software sales representatives without college degrees and age above $40,$ bin the Certificates variable into three groups with equal intervals. Label the groups $1,2,$ and $3,$ with Group $1$ including sales representatives with the most number of certificates and Group $3$ including sales representatives with the least number of certificates. How many sales representatives are in each certificate group for each NPS group?

$\backslash$table$[[$Certificate Groups:,Group $1,$Group $2,$Group $3],[$NPS $8,,,],[$NPS $9,,,]]$