SPORT: Which sport has 'drop-outs' and 'conversions'?

Questions

_The Mousetrap_ opened its London stage run, but who wrote it??

In 1959, which party was elected for the third time in a row in Britain??

Robert Menzies was the Prime Minister of which country throughout the 50s??

Robert Menzies was the Prime Minister of which country throughout the 50s??

The 1951 Festival of Britain was centred on which city??