What’s x, and/or how do i find it?

Find the midpoint of the segment with the given endpoint k(-4,4) and l(6,12)

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?