1. The grid reference index of the map to the east of (3124BB) would be (3125BB).
Latitude: 31° 24' N
Longitude: 118° 24' E
2. To measure the gradient from Δ92 (block C1) to •1526 (block C1), we need to calculate the vertical interval (VI) and the horizontal equivalent (HE).
Δ92 (Block C1):
Elevation: 480m
•1526 (Block C1):
Elevation: 620m
VI = 620m - 480m = 140m
HE = 2 blocks = 2 km
Gradient = VI / HE
Gradient = 140m / 2km
Gradient = 70
3. The gradient of 70 indicates a steep slope. This is because the vertical interval is relatively high compared to the horizontal distance traveled.