Read the following sentences: “If the biochar was going to cost a small fortune, it would not be feasible for local government or nonprofit groups to use in such large amounts. The team went back to the drawing board. They redesigned the biochar tests by increasing the biochar in specific locations.” What does it mean to “go back to the drawing board” in this context?
continue with the same experiment
change the current experiment
design a new experiment
give up on the experiment altogether