Why real image has positive magnification

If m has a magnitude greater than 1 the image is larger than the object, and an m with a magnitude less than 1 means the image is smaller than the object. If the magnification is positive, the image is upright compared to the object; if m is negative, the image is inverted compared to the object

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it