Answer:
Union and Intersection
Step-by-step explanation:
We know that the algebra of sets define the properties and laws of the sets.
The basic operations of sets are,
Union, Intersection, Complement of a set and Equality of sets.
Since, the operations addition, subtraction, multiplication and division are the basic arithmetic operations of numbers.
i.e. they are not in the algebra of sets.
So, we get that out of the given options, the operations in algebra of sets are Union and Intersection.
Answer:

Step-by-step explanation:
Given
--- scale factor
Required [missing from the question]:
The ratio of width of the model to the original
From the question, we understand that the scale factor is: 2 : 15
The ratio of the width of the model to the original equals the given scale factor i.e.
