Answer:
641 m.
Step-by-step explanation:
1 m = .001 km.
1 km = 1000 m.
Combine the already existing m measurements.
100+310 = 410.
Next, convert 1.5km to m.
1.5km = 1,500 m.
Add them both.
1,500 + 410 = 1910.
Finally, subtract and solve.
1910-1269= 641 m.