Which of the sets of ordered pairs represents a function? (4 points) a = {(−4, 5), (1, −1), (2, −2), (2, 3)} b = {(2, 2), (3, −2), (9, 3), (9, −3)} only a only b both a and b neither a nor b

Exercise: counting committees 0.0/2.0 puntos (calificable) we start with a pool of n people. a chaired committee consists of k≥1 members, out of whom one member is designated as the chairperson. the expression k(nk) can be interpreted as the number of possible chaired committees with k members. this is because we have (nk) choices for the k members, and once the members are chosen, there are then k choices for the chairperson. thus, c=∑k=1nk(nk) is the total number of possible chaired committees of any size. find the value of c (as a function of n ) by thinking about a different way of forming a chaired committee: first choose the chairperson, then choose the other members of the committee. the answer is of the form c=(α+nβ)2γn+δ. what are the values of α , β , γ , and δ ?

Ali was paid $75 for mowing a neighbor''s yard. this is one fourth of the amount of money she earned all summer

Ashipment of 18 cars, some weighing 3000lb a piece and th eothers 5000lb each, has a total weight of 30 tons. find the number of each kind of car.