Modern wind turbines are larger than they appear, and despite their apparently lazy motion, the speed of the blades tips can be quite high-many times higher than the wind speed. A typical modern turbine has blades \(56 \mathrm{~m}\) long that spin at \(13 \mathrm{rpm}\). At the tip of a blade, what are

(a) the speed and

(b) the centripetal acceleration?