Title: אופציונלי

Text: Suppose aliens invade the earth and threaten to obliterate it in a year's time unless human beings can find the Ramsey number for red five and blue five. We could marshal the world's best minds and fastest computers, and within a year we could probably calculate the value. If the aliens demanded the Ramsey number for red six and blue six, however, we would have no choice but to launch a preemptive attack. כל פסקה תהיה מבחן.

Save test: השתמש בזה אם אתה רוצה לשתף את המבחן הזה בהקלדה (רק למשתמשים מאומתים).