Question

how did the new weapons introduced in world war i contribute to a war of attrition?
machine guns and powerful, long - range guns led to armies attempting to wear down an enemy to the point of collapse.
the sinking of merchant vessels by u - boats contributed to the blockade and starvation of nations at war.
mustard gas and other forms of chemical warfare created new industries in science that focused on soldiers safety.
the introduction of airplanes on the battlefield made armies less dependent on infantry and mounted soldiers.

Explanation:

A war of attrition is a military strategy where the goal is to wear down the enemy through continuous attacks and resource depletion. Machine guns and long - range guns allowed armies to engage in prolonged firefights, making it difficult for either side to advance quickly. This forced a focus on wearing the enemy out. U - boats sinking merchant vessels contributed to a blockade, which is a key aspect of attrition warfare as it aims to starve the enemy of resources. Chemical warfare (mustard gas) and the introduction of airplanes are more about new forms of warfare rather than directly contributing to the war of attrition concept of wearing down the enemy through continuous, resource - draining engagement.

Answer:

Machine guns and powerful, long - range guns led to armies attempting to wear down an enemy to the point of collapse.
The sinking of merchant vessels by U - boats contributed to the blockade and starvation of nations at war.