Before starting the game answer the following questions:

Q.1

How many coins do you get every of the 20 rounds ?

20
10
5
Other / not clear from instructions

Q.2

If you contribute 5, what is the lowest payment you are guaranteed from this round ?

5
7.5
10
Other / not clear from instructions

Q.3

If you contribute 5, and all others do the same, how much are you guaranteed from this round ?

7.5
15
20
Other / not clear from instructions

Q.4

Given the following setup:

Player/sContribution to Group Account
You5
Other 7 players5
Other 4 players10
Other 4 players0

what will your position be in the ranking ?

I am equally likely to take any rank
I will always be ranked between the 5th and 12th positions (all equally likely for me), and never a higher or lower rank
On average I will be ranked in the middle (my expected rank is 8.5)
Other / not clear from instructions