Question: 1. Find a minimum-weight spanning tree of the graph shown in Figure (and mention which algorithm you used to produce it).
2. Which one of the following statements is true (and why)?
(a) -3 ≡ 21 (mod 12).
(b) -3 ≡ 15 (mod 12).
3. Let a function from the real numbers to the integers be defined by f(x) = x. Is f one-to-one? Is f onto? Explain why or why not in each case.