Add spaces: Heobtainedtheequationsofmotionfortheangularmomentumandforthecentreofmasswitharbitraryexternalforces.

Answer: He obtained the equations of motion for the angular momentum and for the centre of mass with arbitrary external forces.

Add spaces: *SomeOHPfileextensionformatscanbeopenedinbinaryformatonly.

Answer: * Some OHP file extension formats can be opened in binary format only.

Add spaces: Listofproductsoforigin:Niger

Answer:
List of products of origin:Niger