Hello everyone! I just was reading Your questions and was interested in IAO problems. There are only problems without solutions of 2011 year in the net, but i found IAO 2005 problems. So i can not understand how to solve some of them. Like humans, astronomers of venus use the same method for definitions of parallaxes and of parsec but measure them in different (their own) units. For example, the distance to Sirius equals to 19.6 vpc (venusial parsec). -Describe the most evident system of angular units used by astronomers of venus. -Calculate the venusial diurnal parallax of the Sun. Citizens of venus have two hands as humans and 7 fingers at each hand. Thank you for comments!