(a) 50% by definition of the mean as the central point of the distribution.
(b) For Z=1 the table gives the value 0.8413 which is 0.3413 above 0.5000 (mean). So 34.13% is the probability of being in the range from the mean and 1 SD from the mean. 0.5000-0.3413=1-0.8413=0.1587 (15.87%) is the probability of the height being at least 1 SD from the mean.
(c) 0.9987 is the probability for Z=3 SD from the mean, so 1-0.9987=0.0013 (0.13%) is the probability for the height in excess of 3 SD.
(d) 0.9332 is the probability for Z=1.5, so 0.4332 (43.32%) is the probability of being within 1.5 SD of the mean.