Answer:
44%
Step-by-step explanation:
The average power of a wave is directly proportional to the square of the frequency.
P ∝ ω²
Writing a proportion:
P₁ / P₀ = ω₁² / ω₀²
P₁ / P₀ = (1.2 ω₀)² / ω₀²
P₁ / P₀ = 1.44
P₁ = 1.44 P₀
The power increases by 44%.