Answer:
![\sf a. \quad Scale\;factor=(10)/(9)](https://img.qammunity.org/2023/formulas/mathematics/high-school/9bkt4fl8muopaahhbmaz6qauou3821ncg0.png)
b. Enlargement.
Explanation:
The original figure is called the "pre-image".
The new, transformed figure is called the "image" and is usually indicated by the addition of ' after the name.
Therefore:
- CP is the pre-image.
- CP' is the image.
To find the scale factor of dilation, divide the dimension of the image by the dimension of the pre-image.
![\implies \sf Scale\;factor=(CP')/(CP)=(20)/(18)=(10)/(9)](https://img.qammunity.org/2023/formulas/mathematics/high-school/zib8359nny2le1tp71f9etct439mp5cxwz.png)
As the image is larger than the pre-image (and the scale factor is larger than 1), the dilation is an enlargement.