Answer:
More than 60% of the soldiers on both sides were lost at Gettysburg = FALSE
Neither the Union army nor the Confederates lost as much as 60% of their force with the highest being the Confederates who lost about a third of their army
Stonewall Jackson was accidentally shot by his own men prior to the battle of Gettysburg = TRUE
Stonewall Jackson was shot by his own men as he approached camp and died subsequently. This happened just shy of two months before the battle of Gettysburg.
The battle of Gettysburg started because Confederate soldiers were looking for shoes = TRUE
Some Confederate soldiers had gone into Gettysburg to look for supplies including shoes when they encountered the Union army and in the process of gaining reconnaissance, the battle started.
After suffering serious losses, Lee retreated with his army back to Virginia in pelting rain. = TRUE.
General Meade correctly predicted Lee's strategy and inflicted heavy losses on the Confederates, forcing Lee to retreat back to Virginia as the rain pounded them.