It is the air which you are respirating till now
The backhanded hit would be a low hit not a high hit.
The HPV vaccine only prevents from certain types of HPV, usually the most common ones that cause cancers and genital warts. It does not cure the cancer or eliminate the virus from the body.
In this situation, the nurse should assess the therapy to have a positive response when oxygen saturation levels are at 98%.
Pre-mature babies is said to have immature lungs which will definitely mature on the 36th week of gestation. So with the case of the baby in this question, surfactant therapy is given to the premature baby in order to survive. With this therapy, it will help the premature baby to receive oxygen and to release the carbon dioxide in the baby's body.