With what maximum speed can a motorcyclist ride on a horizontal road, describing an arc with a radius of 90 m

With what maximum speed can a motorcyclist ride on a horizontal road, describing an arc with a radius of 90 m when cornering, if the sliding friction coefficient is 0.4? What should be the angle of the motorcycle rider?

Given R = 100 m
u = 0.4
Decision:
ma = mg + N + Ftr
x: mV ^ 2 / R = F tr.
y: 0 = N-mg
Ftr = uN
V = ugR = 0.4 * 10 m / s * 100 m = 20 m / s
tg a = Ftr / N = 0.4
a = arctan 0.4 = 20 degrees (approx)
Answer: V = 20 m / s, α ≈ 20 °