Agravitational force can be described as?
a. the amount of mass contained in an object
b. the attraction between objects with mass
c. a pull felt by matter that is under high-pressure
d. the push needed to pack matter into a volume

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Brendan made a diagram to compare and contrast the benefits of two types of social behavior. which description belongs in the area marked "z"? reproductionprotectionforaginghydrodynamic efficiency

The wind speed in the region between cities a and b was probably the greatest at noon on which day