How did the tradition of trick or treating start?

In simplified exponential notation, the expression a^2•a^-3•a 1/a 0

Acarnival sold tickets for $1.50 for adults and $1.00 for students. there were 54 tickets sold for a total of $70.50. write a system of equations to represent the number of adult tickets,x, and the number of student tickets,y. find the solution and explain what it means. i'll you if you me

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?