{
  "correct_letter": "D",
  "correct_formula": "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)",
  "annotation": "Environment: g=-9.81, F_drag=0.0\nGround: e = 0.4\nCopperSphere: d = 2.0, e = 0.45, h = 1.0, v_0 = (0.0, 0.0, 8.0)\nSilverSphere: d = 2.0, e = 0.4, h = 1.0, v_0 = (0.0, 0.0, 8.0)",
  "choices": [
    "h_next = e²·h_current",
    "B = μ_0·I / (2π·r)",
    "y = h·cos(g·x / v_0²) + x·tanθ",
    "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)"
  ],
  "correct_index": 3,
  "physics_type": "Projectile",
  "seed": "Projectile|benchmark/projectile/1"
}