Will walks his dog around the block he spend an hour walking and make it 4km what is there speed

Speed = distance ÷time
speed = 4÷1=4
the answer is 4 km/hour

Alterations to the electron-based ionic or covalent bonds between ions or atoms happen during a chemical change. Such changes result in one or more new substances with different physical and chemical properties. This type of change stands in contrast to physical changes which, despite sometimes closely resembling chemical changes, only produce a change in physical properties.