What mass (in kg) of iron must be placed on top of the wood block so that the wood block is just barely submerged (the top of the block of wood is level with the surface of the water and the iron on top is in the air). draw a picture of the situation before you attempt to solve the problem. the density of the wood is 620 kg/m3 and the density of the water is 1000 kg/m3.

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

the best answer for these questions would be:

1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.