The 4 litres of red has to be 2 parts of the mixture, so each part will be 2 litres. Therefore 3 parts of cream will be 6 litres and the one part of blue will be 2 litres.
I hope this isn't too late! You can find the answer to this by first finding the area of the circle, A=πr². So since the radius is 10, we input that into the equation to get π100. Now, there is 360° in a circle and a sector of 90° is 1/4 of it. So to answer the question all you have to do is find 1/4 of the area of the circle.
The answer is π25.
To solve the other questions on your assignment just think about how much the sector is of the full 360° of the circle, for example 180° is 1/2 of the circle or 270° is 3/4 of the circle, and multiply the fraction by the area of the circle.
Hope this helped, good luck! :)
Answer:
Give it a bit of time OK I will say the answer is in the *c'h_a-t