To calculate the volume of sand loaded in the rectangular dump truck, we use the formula for the volume of a rectangular prism, which is:

V = length times width times height

Given:
1. Length of the dump truck = 3.5 m
2. Width of the dump truck = 2 m
3. Height of the dump truck = 0.5 m

Substitute the given values into the formula:
V=3.5 times 2 times 0.5
V=3.5 times 1 (Since 2 times 0.5 = 1)
V=3.5m3


Therefore, the volume of sand loaded in the dump truck is 3.5 cubic meters (m³).