Explicacion
m = 65 kg
g = 10 m/s²
r = 0.5 cm (1m / 100 cm) = 0.05 m
A = π r² = π (0.05 m)² = 0.00785 m²
F =W = m g = 65 kg(10 m/s²) = 650 N
P = F/A = 650 N / 0.00785 m² = 82802.54 N/m²
B low frequency it is the lowest frequency
Artificial gravity is created by rotating the cylinder
So here we can say that the acceleration is due to centripetal acceleration
So here we know that the formula of centripetal acceleration is given by

so here we know that


now we will plug in all values



So above is the radius of the cylinder
Now to find the diameter



so its diameter is 194.8 m
Thats a hard one, From The looks of it, it looks like B, Because it would leave a gap in the flow for a small amount of time