What precent of all species that have ever existed are now thought to be extinct?

Hydrogen has only one electron in its only (and outer) electron shell. if a hydrogen atom were to absorb a small amount of energy, where would bohr say the electron would go? a. fly off the atom b. nowhere, it would just speed up. c. spiral inwards towards the nucleus d. move up to another shell that would form

This problem has been solved! see the answerbuilding a sea wall to prevent ocean water from encroaching on a city is an example of climate change [ select ] ["sequestration", "mitigation", "vulnerability", "adaptation"] .creating a carbon tax to provide incentives to reduce co2 emissions is an example of climate change [ select ] ["sequestration", "mitigation", "vulnerability", "adaptation"] .planting more forests is an example of enhancing carbon [ select ] ["sequestration", "mitigation", "vulnerability", "adaptation"] .the tendency to be adversely affected or lack of ability to adapt defines climate change [ select ] ["sequestration", "mitigation", "vulnerability", "adaptation"] .sequestration, adaption, mitigation, vulnerability

Red blood cells are responsible for transporting oxygen in the blood. people with sickle cell anemia were born with a defective gene that results in sickle-shaped red blood cells. individuals with the disease often suffer pain in their extremities due to the build-up of these cells causing blockages in the blood vessels. the shape of the blood cells also reduces the amount of oxygen transported in the blood.