okay so i think it would take too long for me to write out completely but essentially, you want to break these complex shapes into easier shapes that you know how to calculate the area for.
for example, 1)
you can split it into 3 different rectangles...
the rightmost is 4.5cm by 5cm
the middle is 5cm by 6.5cm
and the leftmost is 2cm by 4.5cm
once you've calculated all their areas seperately, add them all together and that'll be the total area of the object
hope this made sense ;)
