Answer:
$30 - same
$40 - same
$50 - less
Explanation:
Price ceiling is when the government or an agency of the government sets the maximum price for a good or service.
Price ceiling is binding when the price is set below the equilibrium price for that good.
An equilibrium price of $30 is less than $40, so the price ceiling isn't binding and there would be no effect on the number of people attending the concert. Same argument applies when equilibrium price is $40.
Equilibrium price of $50 is greater than price ceiling. This would lead to an increase in demand over supply causing a shortage. This would cause a reduction in the number of people that attend concerts.
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