From cloning to 3D printing, what if we could actually make copies of ourselves?

Imagine if we had a thermostat that could turn the world temperature down - could we fix global warming? But be careful, a few degrees too far and could cause an ice age.

Imagine if we had a thermostat that could turn the world temperature down - could we fix global warming? But be careful, a few degrees too far and could cause an ice age.