Let there be an agent with memory that can move within a plane. From its sensors, it receives at clock ticks of a regular interval Dt its exact position (x, y) in Cartesian coordinates.

 (a) Give a formula with which the agent can calculate its velocity from the current time t and the previous measurement of t − Dt. (b) How must the agent be changed so that it can also calculate its acceleration? Provide a formula here as well