Do not use the opposing lane to pass another vehicle unless you have at least _______ of clear roadway ahead of you.

Explanation

According to the Oklahoma Driver's Manual, you should not use the opposing lane to pass another vehicle unless you have at least 200 feet of clear roadway without a no-passing zone or oncoming vehicles. (Note: Even 200 feet is cutting it rather close. If your vehicle and an oncoming vehicle are each traveling at 40 mph, the two vehicles will close a 200-foot distance between them in just 0.9 seconds, after which the two vehicles may collide head-on. Try to avoid passing unless the opposing lane is clear for a great distance.)