Eₐ = 44.6 kJ·mol⁻¹
Use the Arrhenius equation
ln(k₂/k₁) = (Eₐ/R)(1/T₁ -1/T₂)
ln(5.90× 10⁶/3.58 × 10⁵) = (Eₐ/8.314 J·K⁻¹mol⁻¹) (1/527 K - 1/727 K)
ln16.48 = (Eₐ/8.314J·mol⁻¹) × 5.220 × 10⁻⁴
2.802 = Eₐ ×6.729 × 10⁻⁵ mol·J⁻¹
Eₐ = 2.802/(6.729 × 10⁻⁵ mol·J⁻¹) = 4.46 × 10⁴ J·mol⁻¹
Eₐ = 44.6 kJ·mol⁻¹