You have two boxes of colored pens. the first box contains a red pen, a blue pen, and a green pen. the second box contains a yellow pen, a red pen, and a black pen. what is the set that represents all the pens?
a.{red pen, blue pen, green pen}
b.{red pen}
c.{red pen, red pen, green pen, yellow pen, black pen}
d.{red pen, blue pen, green pen, yellow pen, black pen}

The investigating team suspected that there were differences in the cost of repairing cars in workshop i and workshop ii. the investigating team suspected that the costs raised by workshop i were greater than workshop ii. for that they tested the repair of 15 cars in each workshop to see the cost of repairs.the decision of the right hypothesis to prove the suspicion above is a. h0 : μ1- μ2­ = 0; ha : μ1- μ2­ ≠ 0 b. h0 : μ1- μ2 ≥ 0; ha : μ1- μ2 < 0 c. h0 : μd ≥ 0; ha : μd < 0 with μd = μ2- μ1 d. h0 : μd = 0; ha : μd ≠ 0 with μd = μ2- μ1 e. h0 : μ1- μ2 = 0; ha : μ1- μ2 ≥ 0