Achange in the earths core would have a greatest effect on?

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant

An object is 10. cm from the mirror, its height is 3.0 cm, and the focal length is 2.0 cm. what is the image height? (indicate the object orientation by including the + or - sign with the answer.) hi = cm +1.33 -1.33 +0.75 -0.75

What is an aquifer for science class