<p>U ovom radu ćemo pomoću planarnih grafova napraviti klasifikaciju pravilnih poledara i vidjeti&nbsp;<br />jo&scaron; neke mogućnosti primjene grafova u geometriji.</p>

<p style="text-align: justify;">PowerPoint is a popular classroom tool to make simple presentations. Such presentations can be flat when creating interactive lessons for students to use while sitting in front of the computers. Using built-in scripting features, Visual Basic for Applications, the interactivity of PowerPoint can be extended to unlimited dimensions. This paper has to aim to introduce basic scripts needed for modeling quiz questions and it is focused on educators<br />with little or no programming background. Quiz questions can be an important part of the e-learning.</p>

<p>U ovom radu predstavljamo teoriju grafova i njen značaj u matematici i drugim<br />oblastima nauke i dru&scaron;tvenog života. Grafovi sečesto upotrebljavaju za opis i grafički prikaz<br />apstraktnih modela i struktura podataka. Takav pristup olak&scaron;ava njihovo razumijevanje. Budući<br />da teorija grafova ima veliku primjenu u informatici, njen razvoj zadnjih decenija je ubrzan.<br />Kroz ovaj radćemo prezentovati nekoliko jednostavnijih primjera primjene teorije grafova u<br />različitim oblastima, sa ciljem popularizacije teorije grafova.</p>

By means of zeta and normal zeta functions of space groups, we determine the number of subgroups, resp. normal subgroups, of the tenth crystallographic group for any given index. This enables us to draw conclusions on the subgroup growth and the degree of this group.

We calculate zeta and normal zeta functions of space groups with the point group isomorphic to the cyclic group of order 2. The obtained results are applied to determine the number of subgroups, resp. normal subgroups, of a given index for each of these groups.