Why is it difficult to determine earth's inner structure

Scientists can't determine because it's far to fragile and hot to dig into the earth therefore we don't know exactly how it is just can give an estimate based on what we already know from the other layers

Mexico has a host of environmental problems, including significant chemicalpollution  from factory discharges and waste dumping, but the main threat to itsbiodiversity  probably stems from  deforestation  and other natural habitat losses. forest habitat is lost for a number of reasons