Amutant strain of e. coli produces β-galactosidase in the presence and in the absence of lactose. where in the operon might the mutation in this strain occur and why?

“other instruments such as gravimeters and magnetometers are also used in the search for petroleum. extracting crude oil normally starts with drilling wells into an underground reservoir. when an oil well has been tapped, a geologist (known on the rig as the "mudlogger") will note its presence. “ this is what i found on google i hope it