You and your friend part at an intersection. Your friend drives away north at a constant speed. You linger at the intersection for an hour, and then drive off due east at a speed that is 10 miles per hour faster than your friend's speed. Two hours after your friend's departure the distance between the two of you is 130 miles. 4 hours after your friend's departure your distance from your friend is miles. (Remember that ww expects your answer to be within one tenth of one percent of the true answer.)