A store sells a one day two hour children events tickets. Once-a-week on sale starts on Monday. Monday to Wednesday demand for the tickets can be approximated by a normal probability distribution with a mean of 500 and a standard deviation of 120. The tickets cost $1:50 each, and the store sells them for $3 each.

(a) If the store throws out all unsold tickets at the end of Wednesday, how many tickets should be ordered?

b) If the store reduces the ticket price to $1 each at the end of Wednesday and can sell all surplus tickets at this price, how many tickets should be ordered?

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