Answer
a) Please see the image.
b) $8/17$ is P(female | ends in vowel); P(ends in vowel | female) = $8/20$
c) Females are more likely to have names ending in vowels.
d) It makes more sense to have the gender as the first variable as that resulted in higher probabilities.
Work Step by Step
b)
40 students were surveyed--20 boys and 20 girls. 9 boys has vowel endings, and 8 girls had vowel endings.
17 total students have vowel endings.
$8/17$ is P(female | ends in vowel)
20 female students, and 8 have vowel endings
$8/20$ is P(ends in vowel | female)