When an antigen attacks the body, it activates adaptive immunity. this adaptive immunity produces a strong response when it encounters the same antigen for the second time. which feature of adaptive immunity is essential for this kind of response?
a.
the ability to remember the antigen it encounters
b.
the ability to distinguish between self and nonself antigens
c.
the ability to produce nonspecific antibodies against the foreign antigen
d.
the ability to secrete lysozymes against pathogenic antigens

An electron is ejected into a horizontal uniform e⃗ field at a parallel horizontal velocity of v0. assume the electron's initial position x0, initial velocity v0, time t, magnitude of electric field e, electron's mass m, and the magnitude of the electron's charge |e|. ignore the force that earth exerts on the electron. assume the e⃗ field is in the same direction as the initial velocity. part a define the equation for the electron's velocity. express your answer in terms of the variables v0, |e|, t, e, and m.