Which word best describes the vikings?

The word that best describes the vikings is ferocity.

battle of saint-mihiel, (12–16 september 1918), allied victory and the first u.s.-led offensive in world war i. the allied attack against the saint-mihiel salient provided the americans with an opportunity to use their forces on the western front en masse.

explanation:

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)