Darla can complete a job in 8 hours, while lonnie can complete the same job in 6 hours. Both darla and lonnie begin working on the job together. After working together for 3 hours, how much of the job is left to be completed? express your answer as a common fraction.

What percentage of the earth's water is available for use by living things?

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.

Scientists observed a rock stratum with fossil. if mollusks evolved before arthropod, where will their fossils be found.