Elena needs a passport photo that meets certain requirements to be used. One of the requirements is that the measurement from her chin to the top of her head is between 25 millimeters and 35 millimeters in the photo.

Elena has a photo of herself in which that measurement is 150 millimeters, and she has access to a photocopier that can reduce the height of the photo to 80% of its previous value each time it is copied.

1. Find the measurement from her chin to the top of her head after the image has been scaled by 80% these number of times. Explain or show your reasoning.
   1. 3 times
   2. 6 times
2. How many times would the image need to be scaled by 80% for that measurement to be less than 35 mm?
3. How many times would the image need to be scaled by 80% for it to be less than 25 mm?