Two objects are placed in a tank of water (density of 1.0 g/mL). Object A sinks, while object B floats. Which of the following statements must be true?
I. Object A must be less dense than object B.
II. Object A must be more dense than object B.
III. Object B must be less dense than the water.

A33.1 g copper object is launched from a 1.5 m 30° steel incline positioned on the floor by being pulled up a string attached to a 50.0 g mass suspended vertically over a pulley. the object is projected towards a glass table where it lands when it is at the point along its trajectory with the lowest speed. it comes to a halt when it clears the opposite edge of the table. it then falls and lands on 9 physics texts each 5 cm thick that are stacked on the floor on the opposite side of the table. assume that the table does not have a ledge and the rectangular object experiences 0.05 n of air resistance as it falls towards the books. how far and how long did the object travel and how fast does it hit the books. assume that at the moment the copper object leaves the incline, the massless string and ideal pulley break off

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

Excuse ! extra points plus ! super desperate ! the position of an object does not move relative to a reference point. relative to the reference point the object _. a.) is not moving. b.) is moving.