#### Answer

Fraction change in area: $0.00792$
Percentage decrease in area: $0.792$

#### Work Step by Step

We know that fraction change in area is given as
$\frac{\Delta A}{A}=2\alpha \Delta T$
We plug in the known values to obtain:
$\frac{\Delta A}{A}=2\times 12\times 10^{-6}\times (-330)=0.00792$
Now the percentage decrease in area is given as $\frac{0.00792\times 100}{100}=0.792\%$