Explain some of the factors that make it difficult for geologists to learn about the precambrian era?
can you , really

There is not much Precambrian strata preserved and very few species.  At this particular time, the earth, and the creatures in it, were still evolving and fossils were difficult to trace and record.  There was also a noted mass extinction that occurred.  Also, many Precambrian rocks have been heavily metamorphosed, obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata