Which of the following is not a factor in efficiency?
a.
metabolism
b.
type of movement
c.
muscle efficiency
d.
digestion

need someone who's already answered the question

Astructural difference between the trachea and esophagus that prevents the trachea from collapsing is the presence of: a) smooth muscle b) skeletal muscle c) respiratory cilia d) rings of cartilage

So i have a lot of answers answered but it says i still need to answer more questions. why is it doing that? how many questions need to be answered?

Which of these is a long-term goal? a. i want to lose two pounds in a month. b. dylan wants to finish reading his favorite book this week. c. thomas plans to invite his parents to his home for dinner. d. daisy wants to write a children’s book on nutrition