[填空题]
A neuron is stimulated with an electric 2ukb1 xqd1ty 0pulse. The asak0) flf 74 s 75fjxup1fm9fyction potential is detected at a point 3.40 cm down the axon 0.0052 s later. When the action potential is detected 7.20 cm from the point of stimulation, the time required is 0.0063 s. What is the speed of the electric pulse along the axon? (Why are two measuref 4j)sl7xf5km70af fy1p sf9uments needed instead of only one?) m/s
