Arrange the steps in order to describe how photons and carbon dioxide (CO2) contribute to the warming of Earth. CO2 in the atmosphere absorbs infrared
photons.

CO2 in the atmosphere emits infrared photons back toward Earth.

Photons from the Sun strike Earth and become infrared photons.

Earth radiates infrared photons into the atmosphere

The Sun radiates sunlight (visible)
photons

The Sun radiates sunlight (visible)  photons

Photons from the Sun strike Earth and become infrared photons.

Earth radiates infrared photons into the atmosphere

CO2 in the atmosphere absorbs infrared  photons.

CO2 in the atmosphere emits infrared photons back toward Earth.

Certain gases are known to contribute towards global warming. Such gases are called greenhouse gases. The infrared rays from the sun are absorbed by these gases as they are re-emitted from the earth and re-emitted.

The sun radiates photons to the earth which is re-radiated into outerspace from the earth's surface. CO2 and other greenhouse gases absorbs these gases and re-emit them to the earth thereby causing a gradually rise in the temperature of the earth called global warming.

what is the general relationship between a galaxy's distance from earth and its speed?

the answer is:

the farther away a galaxy is from us, the faster it is moving away from us.