Back in 1953 the U.S. Army started an experimental programme of food irradiation so that deployed troops could have fresh food without refrigeration. The procedure is a simple one. Food is exposed to high levels of radiation to kill insects and harmful bacteria. It is then packaged in airtight containers, in which it can be stored for months without deterioration. The radiation sources for most food preservation are cobalt-60 and cesium-137, both of which are γ -emitters, although X-rays and electron beams can also be used to irradiate food.

Read the above passage and answer the following

questions.

(i) Match the radioisotopes with their application from the alternates given :

Radioisotopes Applications

Ι . Cobalt-60 P. Leukemia therapy

ΙΙ . Potassium-40 Q. Thyroid therapy

ΙΙΙ . Iodine-123 R. Geological dating

Ι V. Phosphorus-32 S. Cancer therapy

V. Carbon-14 T.Archeological dating

I II III IV V