Where n represents the position in the sequence

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?  

Solve 4 ln x=2ln25 a) x=5 b) x=25 c) x=625

Acircle has a radius of 12.6cm what is the exact length of an arc formed by a central angle measuring 120