A physics book is moved once around the perimeter of a table of dimensions 1 m by 3 m. If the book ends up at its initial position, what is the magnitude of its displacement?

Year  1936,  lehman predicted that the earths 'inner core' is solid. she observed that the seismic signals during her study were bent and did not pass through instead bouncing back. later it was confirmed that the earth's inner core was solid made up of nickel-iron and had a molten outer core.

Ai think hope that