Step-by-step explanation
From the statement, we know that the probabilities of the events U and D are:
• P(U) = 0.71,
,
• P(D) = 0.29.
If we flip the thumbtack two times, we have four possible results:
0. UU,
,
1. UD,
,
2. DU
,
3. DD.
Because the result of each flip is independent of the other, the probability of each arrangement is the product of the probability of each event:

Answer
D. There are four arrangements: UU, UD, DU, and DD. The probabilities are:
• P(UU) =, 0.5041
,
• P(UD) = ,0.2059
,
• P(DU) =, 0.2059
,
• P(DD) =, 0.0841