Query: Elements affected by a given activity.Purpose: Returns the elements that are sources of basic transitions in the input liststm_r_mx_source_of_ bt (stm_list in_list,
int *status);
Query: Elements affected by a given activity.Purpose: Returns the elements that are targets of basic transitions in the input liststm_r_mx_target_of_ bt (stm_list in_list,
int *status);