I) The Phys.SE question Resistance of circle of wire indeed seems to be question B2 of a homework assignment with due date 30.09.2013 from the FKS secondary school competition in Slovakia.
Google translator from Slovak -> English produced this translation of the pdf file:
B2 - Nákružnica (9 points)
Tinka is seeking revenge, as it pulled beetroot (and gave them Katka). Therefore, pulled out of the lab resistance wire with resistance R and produced from it earring. Sealed iron ends so as to form circle of uniform cross-section. She felt while resistance and resistance earrings a measured so that the earring Conn. ohmmeter between terminals. What minimum and maximum resistance to Tinka measure? What resistance values when the clamps squeezed from the middle of the circle angle α.
It is moreover specifically stated next to a warning skull in the pdf document that Úlohy rieš samostatne!, i.e. the problems should be solved separately.
II) The Phys.SE questions Bubble in a pipeline, Ice cube in a pool, and https://physics.stackexchange.com/q/76091/2451 seem to be problem I.3, I.4, and I.Exp, respectively, of a first round of problems with due date 14.10.2013 from the FYKOS high school competition in Czech Republic.