I got a different answer..
and i don't see it as one of your choices, also your question is confusing since you're repeating it .-.
But anyways i got
The total bill amount before the service fee is given as $45.
We are given that the tip she wants to leave is 15% of the bill amount, this means that:
tip value = 0.15 * 45 = 6.75$
The total bill would be the summation of the original bill and the tip value she left.
Total bill amount = 45 + 6.75 = 51.75$
Answer:
Two letters that don't appear is q and z.