4.
y = 1/120 * x^2 = 90 --> x = -103.9 ∨ x = 103.9
Spannweite sind also etwa 207.8 m
5.
a = - 69/(160/2)^2 = - 69/6400
y = - 69/6400 * x^2
160/8 = 20
[-80, -69;
-60, -38.8125;
-40, -17.25;
-20, -4.3125;
0, 0;
20, -4.3125;
40, -17.25;
60, -38.8125;
80, -69]