The decay of atoms is a source of internal energy for the Earth because is produced in the decay process.

The correct answer is - heat.

Explanation:

Earth has two energy sources internal and external energy. The external energy comes from mainly the sun while the internal energy comes from two major sources gravitation energy of the earth and the radioactive decay of atoms.

The earth's process of decaying atoms is an internal energy source that is provided by the producing heat by the disintegration of natural atoms inside the earth.

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weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

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