Correct.
See Aerodrome Forecast (TAF and TAF3) in the Bureau of Meteorology Aviation Weather Services Knowledge Centre.
Incorrect.
The correct answer is 'there will be Intermittent variations of conditions for periods of less than 30 minutes from the prevailing conditions between 0300 and 0800 UTC'.
See:
The correct answer is '30% probability of visibility restricted to 7 km'.
The correct answer is '250 deg (T), 15 kt'.
See chapter 6 of the Part 91 Plain English Guide.
The correct answer is '5 km visibility, 1,000 ft vertical and 1,500 m horizontal distance from cloud'.
The correct answer is 'every 3 hours'.
The correct answer is 'visibility is 10 km or more, no cloud below 5,000 ft, no cumulonimbus at any height, and no weather of significance'.
See AIRMET in the Bureau of Meteorology Aviation Weather Services Knowledge Centre.
The correct answer is 'when the occurrence, or expected occurrence, of specified enroute weather phenomena are not already included in the graphical area forecast (GAF)'.
See paragraph 5 AIP GEN 2.7.
The correct answer is '022200 UTC'.
To find pressure height: 1013 – 1023 = -10 x 30 = -300, -300 + 1,200 = 900 ft.
Then to find density height: ISA temp = 15 - (900/1000 x 2) = 13.2, ISA deviation = 30 - 13.2 = 16.8, 16.8 x 120 = 2,016, density height = 2,016 + 900 = 2,916 ft.
The correct answer is '2,900 ft'.
The correct answer is 'when one set of prevailing weather conditions is expected to rapidly change to a different set of prevailing weather conditions'.