Answer:
a) r = 6122 m and b) v = 32.5 m / s
Step-by-step explanation:
a) The train in the curve is subject to centripetal acceleration 
 a = v2 / r 
Where v is The speed and r the radius of the curve 
 
They indicate that the maximum acceleration of the person is 0.060g, 
 a = 0.060 g 
 a = 0.060 9.8 
 a = 0.588 m /s²
 
Let's calculate the radius 
 v = 216 km / h (1000m / 1km) (1 h / 3600 s = 
 v = 60 m / s 
 r = v² / a 
 r = 60² /0.588 
 r = 6122 m 
b) Let's calculate the speed, for a radius curve 1.80 km = 1800 m 
 v = √a r 
 v = √( 0.588 1800) 
 v = 32.5 m / s