ASPHALT
This will vary by brand and style carpet.
The roll would have 3600 sq ft of carpet. It is very uncommon to see a roll this large unless it is a thin indoor/outdoor...but even for those that is large. A roll this size would be too large for anyone to move without a carpet pole on a truck. Most mills will not ship carpet larger then about 133.33 sq yards. They will ask you to request cut sizes. Just verify these are coming from 1 dye lot. As to how big the roll would be would depend on the thickness of the carpet. It would be over 4 ft wide easily and with an average plush closer to 5 ft wide.
A hollow ball.....
sq.ft. carpet = 5 rolls x 12ft wide x length of roll in feet.
The small ball
depends on the ball, big ball, small ball? Big ball would roll easier on carpet and grass, small ball would roll easily on carpet.
Wooden floor - less traction
because grass has more friction for ball to roll than dirt.
The data is
The bigger the ball is the farther it will go.
Varibles and controls for does a ball roll faster on grass or dirt
Neither. The ball rolls faster on cement, not grass, or dirt.
the smaller the mass the farther the roll
the smaller the mass the farther the roll
The reason a ball rolls farther on dirt is because the grass has more potenial than dirt because once you roll the ball really hard the ball will slow down on grass and the grass is sometimes standing up and the dirt doesn't have any thing to stop the ball the dirt is is flat unlike the grass.
Dirt, because it has lesser resistance than grass
Probably concrete, but hard packed sand would do pretty well.