When a certain type of thumbtack is tossed, the probability that it lands tip up is 90%. All possible outcomes when two thumbtacks are tossed are listed. U means the tip is Up and D means the tip is Down. Complete parts (a) through (d) below. UU UD DU DD a. What is the probability of getting two Ups? P(two Ups): 0.81 (Round to two decimal places as needed.) b. What is the probability of getting exactly one Up? P(exactly one Up) = 0.18 (Round to two decimal places as needed.) 0. What is the probability of at least one Up (one or more Ups)? P(at least one Up)= 0.99 (Round to two decimal places as needed.) d. What is the probability of at most one Up (one or fewer Ups)? P(at most one Up) = D (Round to two decimal places as needed.)