There was a time when a C meant average. The average GPA at four-year colleges and universities has risen from 2.52 in the 1950s to 3.11 in 2006. And according to Stuart Rojstaczer, a former Duke University professor and founder of GradeInflation.com, GPAs only keep rising. At some colleges, Rojstaczer says, over 50% of the grades given are A's.
Trench warfare was caused by an advance in defensive weaponry. The machine gun was too heavy to be used as a mobile weapon, and therefore was placed into a fixed position. Barbed and concertina wire was also heavily used.
Rating Newest Oldest. Best Answer: Trench warfare was an extremely effective strategy because trenches were a form of defensive warfare. The Germans marched on Paris in 1914, but when they were halted they dug in. From then on both sides fought in trenches and neither side could break through.