All About Carbon Dioxide

CO2 is called a trace gas because it makes ___ less than 1 percent of the atmosphere.

But lately, this beneficial carbon dioxide has taken a lot of ____ for making the atmosphere a bit too toasty.

• harm

• heat

• angry

• steam

Match the following

• algae

• 
• douse

• 
• suffocate

• 
• spew

• 
• sink

• 

CO2 is used in some fire ​ (a)   as a quick, effective way to douse ​ (b)   .

• extinguishers
• flames

After months of preparation, the company is finally ready to _____ their new product.

• perform

• display

• release

• remind

Just like the glass walls of a ​ (a)   trap heat inside a building’s structure, CO2 acts like a ​ (b)   to hold heat close to our planet’s ​ (c)   . Earth would be​ largely ​ (d)   without it.

• greenhouse
• blanket
• surface
• uninhabitable

The success of the project can be attributed _____ to the hard work of the team.

• quickly

• largely

• reluctantly

• loudly

The population of the small town is _____ 5,000 people.

• happily

• approximate

• roughly

• roundly

 In the Earth's ____ past, it is believed that extreme volcanic activity may have led to uninhabitable conditions on the planet

• average

• old

• remotely

• distant

The ____ temperatures on Venus are a result of its dense atmosphere and proximity to the sun.

• blistering

• highly

• blowing