C 57. B 58. A 59. B 60. A C 57. B 58. A 59. B 60. A

56. C 57. B 58. A 59. B 60. A --- G. CLOZE TESTS I. Select the one that best fits the gap Everyone knows that our energy is derived ...(61)…from the sun. It is wiser for mankind to…(62)…it immediately, rather than wait for the slow forces of nature to …(63)…it into fossil fuels. The simplest way is to utilise the flat-plate collector sited on the …(64)… of a house. It operates when pipes on the plate channel water to and from the …(65)…hot water tank. As sunshine rapidly…(66)…the plate, the prevailing heat is absorbed by the water as it passes. A sheet of glass serves a dual purpose - It …(67)…the sunshine in, and traps the infra-red radiation. The plate is kept warm by…(68)… the release of infra-red radiation. It is essential that the sun must be high enough in the sky to …(69) … the water. On cloudy days and in winter a flat-plate collector may fail to provide sufficient …(70)…to warm a full tank of water.