Can anybody PLEASE help with ANY of these discrete mathematics questions??

[whyohwhy]

(a) T F If f is a one-to-one function from an infinite set A to
itself, then f must be onto.
(b) T F If g is a one-to-one function from a finite set A to itself,
then g must be onto.
(c) T F Let A = Z+ the set of positive integers. Define the
relation R on A by aRb if and only if a / b. R is transitive.
(d) T F R the relation from (c) is symmetric.
(e) T F R the relation from (c) is asymmetric
(f) T F R the relation from (c) is antisymmetric
(g) T F R the relation from (c) is irreflexive
(h) T F R the relation from (c) is an equivalence relation
(k) T F Let B = {0,1} with the standard partial order and let
A = B x B x B with the product partial order. Then
A is isomorphic as a lattice to D60
(m) T F Every finite lattice has a least element
(n) T F Every poset has a greatest element
(o) T F f(n) = log5(n) is O(lg(n))
(p) T F If g is the mod-10 function,then g(405)=4
(t) T F If R is a reflexive relation, then the connectivity relation
R(infinity) is equal to the reachability relation R*