They are a teaching aid for showing students how the various planets revolve and rotate. With an Earth/Moon/Sun system model you can answer all these questions by just turning the handle.. 1  Why we have day and night. 2  What a year is. 3  What a lunar month is.  Why there is summer and winter.
Currency. Romania's currency is the leu (usually appears in the plural form lei). It comes in Polymer notes. The currency has changed to RON (Romanian new lei). 1 (green) 5 (purple) 10 (Reddish Brown) 50 (Yellow) 100 )Blue) (200 and 500 lei notes are rarely used). The leu's subdivison is the ban (plural form bani), 1 leu = 100 bani), which comes in 1 (brass), 5 (cooper) 10 (steel) and 50 (brass) bani coins.
For travel around the country it is a good idea to carry cash. Small stores and restaurants might accept U.S. Dollars in small denominations ($ 1, 5, 10 and 20) but the exchange rate offered will not be the best. Street handicraft vendors prefer Romanian currency.