You're Drilling for Oil!

In a few moments, you will see a large lot of land. Under the sand, there may be oil reservoirs. Some reservoirs are deeper or wider than others. You cannot know where reservoirs lie just by looking at the sand. The only way to find oil is by drilling, and you will have 15 opportunities to drill. Your success in finding oil will determine your score.

When each round begins, choose a spot for drilling and click "drill" within 15 seconds. Then, you will see the amount of oil you found. The amount is indicated by a colored square and a corresponding bar on the left side of the screen. The higher the bar, the better your performance is.

If there are oil reservoirs under the sand, their locations and sizes are determined before the game begins. During the game, the locations and the sizes are not affected by anyone's actions and do not change.

Competitors may also be drilling for oil. If they are present, you will see where they drill, but not how much oil they find.

If you choose to drill in the exact same point as a competitor did, you will find the same amount of oil as the competitor.

After everybody has chosen a drilling spot or 15 seconds have passed, you will advance to the next round. If 15 seconds have passed and you have not made a drilling decision, then you will find nothing in that round.

The game may repeat several times. Whenever a new game begins, the locations and sizes of the oil reservoirs, if any, may shift. Also, your competitors, if any, may change.

The only way to find oil is by drilling, and you will have 15 opportunities to drill. You may drill once in each of the 15 rounds.

Every game will have one winner: the competitor who found the most oil.

This is an example of the game interface.

This is an example of how oil reservoirs may be laying under the sand. You and your competitors can find the reservoirs only by drilling. You will never see where reservoirs are unless you happen to drill into them.

Please enter your first name. Your name will be visible to the other players.

Before you begin the game, please answer the following questions.

In this game, you're drilling for --select-- diamonds coal oil gold silver

When competitors drill, you --select-- can can not see where they drill and you --select-- can can not see how much oil they found, if any.

How many seconds do you have to make a decision? --select-- 5 10 15 20 22.5

The game advances to the next round after
at least two competitors found oil
everybody chose a drilling point
everybody chose a drilling point or 15 seconds have passed
at least 15 seconds have passed
at least one competitor found oil

Which of these statements is true?
The location and size of oil reservoirs is fixed throughout the game.
The location of oil reservoirs is fixed but the size may change during the game.
The size of oil reservoirs is fixed but the location may change during the game.
The size and location of oil reservoirs may change during the game.
The size and location of oil reservoirs can be deduced from the color of the sand.