Synthetic !?

[princess]

I have purchased a used vehicle and the owners have left the country. I am not sure if they have used Synthetic or regular oil, I am wondering how to figure that out.Given the oil seems to be in good condition, Here is what i am seeing on the inner side of the wind screen. a sticker with the below mentioned information.1. Lubricant: 5W20 (does this mean synthetic or regular or no clue ?)2. Date: 07.01.2010 (is this the due date or the date of oil change?)3. Mileage: 142000 (current mileage is 134. why is it due after 8k ?)Any help would be great. The data on the sticker doesnt make sense at all so i thouhgt id check if anyone has experience on how green and ross place their information on their labels after oil change ?I am most interested in knowning if there is anyway to find out about the type of oil used (synthetic or regular ?) Thx