maths question, stressing over, please help :'(. best answer 10points?

[jimmy pop]

i got math mock test tomorrow :'( im stressing out and came across this question found difficult, i need your help!

a)(i)in 2004, cost of organising the concert was $385
in 2005 the cost was 10% less than 2004, calculate cost in 2005

(ii)cost of $385 in 2004 was 10% more than 2003
calculate cost in 2003

b)(i) in 2006, the number of tickets sold was 210
ratio= Number of adult tickets : Number of student tickets was 23:19
how many adult tickets were sold

(ii)adult tickets were $2.50 each and student tickets were $1.50 each
calculate total amount received sellig tickets

(iii)in 2006 cot of organising the concert was $40
calculate percentage profit in 2006

c) in 2007, number of tickets sold was again 210
adult tickets were $2.60 and student tickets were $1.40

total amount recieved from selling 210 tickets was $480

how many student tickets were sold...


THERE ARE ALOT OF QUESTIONS BUT, i really need help please , can you explain what steps you did also
ahhh please help $hive (im stupid when it comes to math)