Why was the steel-faced plow an important invention?

After studying french for 5 yearscin school, i was shocked to discover when i went to france that i couldn't even get a glass of water without a lot of sign language what is the author main point

Dan runs a busy desktop-publishing company. his company want to increase its exposure, so it runs a new a new promotion each week. the tool dan most likely choses to publicize this is a promotion is a

Case # 51173878 weighs 814 pounds; case # 51173981 weighs 803 pounds; case # 51174058 weighs 817 pounds; case 51174178 weighs 815 pounds; case # 51174248 weighs 817 pounds; case # 51174495 weighs 781 pounds; case # 51174577 weighs 828 pounds. what are the case #'s of the two cases that weigh the same amount?