For the area one, calc the areas of the blank areas then subtract from the rectangle.
Or find PBC (or CPB) as its basically the same thing.
It's a 1 marker, don't overthink it.
© Copyright The Student Room 2017 all rights reserved
The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.
Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE