Answer:
 α = 0.357 ras / s²
Explanation:
This is a rotational kinematics exercise, it tells us that it performs 10 squats in 30 s, for which it performs one squat at t = 3 s, also indicates that the angle of the squat is θ = 92º
      θ = θ₀ + w₀ t + ½ α t²
the athlete starts from rest, whereby w₀ = 0 and the initial angle in the vertical position is zero (θ₀=0)
      θ = ½ α t²
      α = 2 θ /t²
let's reduce the magnitudes to the SI system
      θ = 92º (π rad /180º) = 0.511π rad
let's calculate
      α = 2 0.5111π /3²
      α = 0.1136π rad / s²
      α = 0.357 ras / s²