Shriya should consider refrigerators that are less than or equal to the space she has available, which is 26 ft³. Since she currently has a refrigerator with a volume of 20 ft³, any refrigerator that fits within the space she has available would be appropriate.
To ensure a good fit, it's common to leave some space for ventilation. A good rule of thumb is to consider refrigerators that are around 1 to 2 ft³ less than the total available space. Therefore, it would be reasonable for her to consider refrigerators that are between:
20 ft³ and 25 ft³.
So, she should consider refrigerators that are between 20 ft³ and 25 ft³.