In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

What is a computer program sometimes sitting idle until?, Context: Seemingly, multitasking would cause a computer that is switching between several programs to run more slowly, in direct proportion to the number of programs it is running, but most programs spend much of their time waiting for slow input/output devices to complete their tasks. If a program is waiting for the user to click on the mouse or press a key on the keyboard, then it will not take a "time slice" until the event it is waiting for has occurred. This frees up time for other programs to execute so that many programs may be run simultaneously without unacceptable speed loss.
for the user to click on the mouse or press a key

What type of ammunition would not have been common in 1940?, Context: Until the 1950s guns firing ballistic munitions were the standard weapon; guided missiles then became dominant, except at the very shortest ranges. However, the type of shell or warhead and its fuzing and, with missiles the guidance arrangement, were and are varied. Targets are not always easy to destroy; nonetheless, damaged aircraft may be forced to abort their mission and, even if they manage to return and land in friendly territory, may be out of action for days or permanently. Ignoring small arms and smaller machine-guns, ground-based air defence guns have varied in calibre from 20 mm to at least 150 mm.
guided missiles

Who is the father of Richard?, Context: Henry the Young King fought a short war with his brother Richard in 1183 over the status of England, Normandy and Aquitaine. Henry II moved in support of Richard, and Henry the Young King died from dysentery at the end of the campaign. With his primary heir dead, Henry rearranged the plans for the succession: Richard was to be made King of England, albeit without any actual power until the death of his father; Geoffrey would retain Brittany; and John would now become the Duke of Aquitaine in place of Richard. Richard refused to give up Aquitaine; Henry II was furious and ordered John, with help from Geoffrey, to march south and retake the duchy by force. The two attacked the capital of Poitiers, and Richard responded by attacking Brittany. The war ended in stalemate and a tense family reconciliation in England at the end of 1184.
Henry