Copper has a density of 9g/cm3. If a piece of copper has a volume of 10cm3, what is its mass? Equation is density = mass divided by volume

Which describes an image that can be produced by a concave lens? the image is real and smaller than the object. the image is virtual and larger than the object. the image is virtual and smaller than the object. the image is real and larger than the object.

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant

The two required components for a generator are