O is the center of the circle shown, which has radius 18 cm. A, B, C and D are points of the same circle. If arc AB has a measure of 80 degrees, arc DC has a measure of 90 degrees, and arcs BC and AD have the same measure, then what is the length of arc BC?​

Ineed big ! the cost of a school banquet is $25 plus $15 for each person attending. create a table, sketch the graph, and write an equation in slope-intercept and point-slope form that gives total cost as a function of the number of people attending. what is the cost for 77 people?