Maths homework Mr P's Group

A - Claire’s mum wants to paint the kitchen using a nice, blue paint, which costs $35 per litre. The room is about 6m x 8.5m with a 2.7m stud. Claire’s mum figures that about 8.5m2 of space is taken up by windows and doorways. Each litre of paint will cover approximately 8m2 of wall. How many litres will she need to paint the kitchen and how much will the paint cost?
B - Claire’s dad also wants to paint the kitchen, and he likes Mum’s paint choice, BUT he wants to put wood paneling on the bottom half of the walls. How many square metres of wood will he need AND how many fewer litres of paint would the family need if they went with Dad’s idea?
C - The wood panels are sold by the lineal metre. They are $13.50/lm and they are 200mm wide. What will the cost of the wood be if the family go with Dad’s design?
D - Whose design is the cheapest and by how much?