All of the following below are possible sources of error in a scientific investigation except for a. using the wrong equipment during the experiment b. discovering new variables as the experiment proceeds. c. completing multiple trials during an experiment. d. not controlling all the variables in an experiment

c. completing multiple trials during an experiment.

An error is mistake or inaccurate result obtained after accomplishment of scientific protocol. Completing multiple trials during an experiment can be a method to remove error from the experiment. A concordant reading in three or more trials can be a conclusive result instead of one attempt.

there really is life in the deepest part

if your own plato the answer is b. the fern transitioned from sporophyte generation to gametophyte generation.