Russians harsh winter weather has come to their aid at times by

On the whole, the Russian winter greatly helped the Soviets in defending the Motherland.

Explanation:

The German troops did not have enough warm winter uniforms, and their military equipment often seized up in the biting cold.

7.03-1.70=5.33 and 6.80+5.09=11.89 and 5.5-3.01=2.49