Calculate the mode of the data set below, if a mode exists. {0.3, 1.5, 3.8, 2.6, 1.5, 9.1, 4.2, 3.8, 1.5, 2.9} a. 1.5 b. 2.75 c. 3.12 d. this data set has no mode.

in counting the number of heads in 4 coin flips, the probability that we get exactly one head is the probability that we get anyone of the following 4 outcomes: httt, thtt, ttht, or ttth. each has probability 1/16, so the probability to get exactly one head in 4 flips is 1/16 + 1/16 + 1/16 + 1/16 = 4/16 = 1/4.