{
  "correct_letter": "D",
  "correct_formula": "y(t) = h + v_0·t + (1/2)·g·t²",
  "annotation": "Environment: g=-9.81, F_drag=0.0\nGround: e = 0.4\nOakCube: a = 2.0, e = 0.5, h = 15.0, v_0 = 0.0",
  "choices": [
    "y(t) = h·(1 - e^(-g·t²/2))",
    "v = f·λ",
    "v_final = -e·v_impact",
    "y(t) = h + v_0·t + (1/2)·g·t²"
  ],
  "correct_index": 3,
  "physics_type": "FreeFall",
  "seed": "FreeFall|benchmark/freefall_newbatch/4"
}