Answer:
Saskatchewan Glacier
Step-by-step explanation:
You want to know the greater rate, 1.5 km in 75 years, or 1320 m between 1923 and 1993.
The rate of glacier recession is the ratio of distance to time:
Saskatchewan Glacier
(1500 m)/(75 yr) = 20 m/yr
Peyto Glacier
(1320 m)/(1993 -1923 yr) = 1320/70 m/yr ≈ 18.86 m/yr
The Saskatchewan Glacier had a greater annual rate of melting.