Certain gases in air are important natural resources that are used in welding. two of these gases are a. oxygen and argon b. hydrogen and fluorine c. chlorine and sulfur dioxide d. nitrogen and carbon dioxide

The phrase references available upon request should appear at the __ of your résumé? a. back b. top c. middle d. bottom

‘all monkeys have tails’ is an absolute statement. t or f

Which statements are true for invasive species? 1. they always stabilize an ecosystem. 2. they’re always successful in adjusting to a new habitat. 3. they often compete with the native species for resources. 4. they have the ability to displace the native species. 5. they’re always pests.