Final answer:
To find the velocity, acceleration, and speed of a particle, differentiate the position function to get the velocity and acceleration, then find the magnitude of the velocity to get the speed.
Step-by-step explanation:
To find the velocity, acceleration, and speed of a particle with the given position function, we can use the formulas for velocity and acceleration:
V(t) = dr(t)/dt

For the given position function r(t) = (6 cos(t), 5t, 6 sin(t)), we can differentiate it to find the velocity and acceleration:
V(t) = (-6 sin(t), 5, 6 cos(t))
a(t) = (-6 cos(t), 0, -6 sin(t))
The speed of the particle is the magnitude of the velocity vector:
speed = |V(t)|
=

=

= 61