- Formation of the Earth's atmosphere around 4.5 billion years ago
- Agricultural revolution around 10,000 years ago
- Moon landing in 1969
Event that occurred billions or millions of years ago
Event that occurred thousands of years ago
Event that occurred decades ago
oxygen builds up in earths atmosphere
carbondioxide levels reach their highest levels on record
the last ice age ended
3 answers
What does a model of the carbon cycle show?(1 point)
Responses
The amount of Earth’s carbon decreases.
The amount of Earth’s carbon decreases.
The amount of Earth’s carbon cannot be determined.
The amount of Earth’s carbon cannot be determined.
The amount of Earth’s carbon increases.
The amount of Earth’s carbon increases.
The amount of Earth’s carbon is constant.
Responses
The amount of Earth’s carbon decreases.
The amount of Earth’s carbon decreases.
The amount of Earth’s carbon cannot be determined.
The amount of Earth’s carbon cannot be determined.
The amount of Earth’s carbon increases.
The amount of Earth’s carbon increases.
The amount of Earth’s carbon is constant.
The amount of Earth's carbon is constant.