Perez sued Dawson for damages arising out of an automobile collision. At trial, Perez called Minter, an eyewitness to the collision. Perez expected Minter to testify that she had observed Dawson's automobile for five seconds prior to the collision and estimated Dawson's speed at the time of the collision to have been 50 miles per hour. Instead, Minter testified that she estimated Dawson's speed to have been 25 miles per hour. Without finally excusing Minter as a witness, Perez then called Wallingford, a police officer, to testify that Minter had told him during his investigation at the accident scene that Dawson "was doing at least 50." Wallingford's testimony is 
admissible as a present sense impression. admissible to impeach Minter. inadmissible, because Perez may not impeach his own witness.  inadmissible, because it is hearsay, not within any exception