Emma and her lab partner were studying how abiotic factors affect organisms. they chose to work with daphnia and study the ph range at which they survived best. they used plastic tubing that could be closed off at each end. 10 daphnia were placed in the tubing filled with water. a 1% solution of hcl was injected into one end of the tubing while 1% solution of koh was injected into the other end. the daphnia were observed in 1 minute intervals for 20 minutes and their behavior (ph preference) was recorded. they conducted three trials.