Ah yes, 1000 year old civilizations, famous for having modern high efficiency photovoltaics.

It’s the derivative of the unit tangent vector at t with respects to t. The unit tangent vector has length 1 and points in the direction the curve is traveling. Since it’s length is fixed at 1, this means the derivative describes how much the direction of the curve is changing with respects to t.

I got you bro. Use one of these formulas

He has to go to bed at 7pm to wake up at 3am and do a 6 hour “morning routine” because he is an “alpha male.”