There are 26 letters in the alphabet, 5 are vowels, therefore, the probability of choosing a vowel the first time is:

and the second time is:

Continuing with this reasoning, we get that the probabilities each time are:

Finally, the probability that you get all vowels is the product of the probabilities:

Writing the above result as a percentage we get:

Answer:
The answer to your question is...
60 times more than a minute!
Total hours worked: 6 + 4 + 8 = 18 hours.
To find her hourly rate, divide the total pay by total hours worked:
130.50 / 18 = $7.25