Answer:
[tex]diameter \: of \: circle = 6 \div 2 = 3[/tex]
[tex]radius = 3 \div 2 = 1.5cm[/tex]
[tex]a \: of \: 1 \: circle = 1.5 {}^{2} \times \pi = 2.25\pi[/tex]
[tex]a \: of \: 4 \: circles = 2.25 \times 4 = 9cm {}^{2} [/tex]
[tex]a \: of \: square = 6 {}^{2} = 36cm ^{2} [/tex]
[tex]a \: of \: rest = 36 - 9 = 18cm {}^{2} [/tex]