**5. Conclusions**

Basing on the results of the research described in the paper, the following conclusions were formulated:


**Acknowledgments:** This research was conducted in the framework of task No. M-4/353/2016/DS, which was a subsidy for research granted by the Ministry of Science and Higher Education of the Republic of Poland. The author of the paper would like to thank Łukasz Rodak from Cracow University of Technology for support in the data acquisition process.

**Conflicts of Interest:** The author declares no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.


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