Which statements best describe shared characteristics? Select two options. Shared characteristics always exist in the common ancestor and in the modern organism.
Shared characteristics never exist in the common ancestor or in the modern organism.
The more characteristics organisms share, the more closely related they are.
The fewer characteristics organisms share, the more closely related they are.
Shared characteristics can exist among organisms that belong to different species.
Shared characteristics only exist among organisms that belong to the same species.

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".