\(=1.3\)
\(\%\) increase \(=\frac{\left(\Delta T _{ f }\right)_{ obs }-\left(\Delta T _{ f }\right)_{ cal }}{\left(\Delta T _{ f }\right)_{ cal }} \times 100\)
\(=\frac{K_f \times i \times m-K_f \times m}{K_f \times m} \times 100\)
\(=\frac{i-1}{1} \times 100=30 \%\)