1. In PET (positron emission tomography) scanning a positron (mass of an electron but opposite charge), from an injected/infused emitter such as ¹⁸F (in a compound such as fluoroglucose), collides with an electron. The positron-electron collision results in annihilation of their masses with complete conversion to two photons of gamma radiation. What is the wavelength of the radiation released in this process? (2 marks)

   	a.	2.4 x 10-12 m
   	b.	1..2 x 10-12 m
   	c.	4.8 x 10-12 m
   	d.	9.6 x 10-12 m