A group is considered polyphyletic if the group does not contain the most recent common ancestor. it is the most parsimonious grouping. all members share homoplastic traits. all members of the group share a common ancestor. not all descendants of the common ancestor are included.

mass and weight are closely related because mass affects the weight of an object experiencing the effects of gravity. weight is the measure of the force of gravity on an objects's mass, while mass is the measure of how much matter there is in an object.

the ems is the abbreviation for the emergency medical services. it is a service provided by a group of medical professionals specialised doctors and other healthcare staff.

any one can call 911 in case of any medical emergency and a group of health care professional will come and give the treatment required. every day the ems staff receive many phone call, which are related to different types of medical emergencies, out of which 25-28% are exclusively related to the respiratory issues.

so, the correct answer is 25-28%.