MATH HW (motion problems)

Ma'am said only do the odd #'s so...
1) Two cars A and B having average speeds of 30 mph and 40 mph respectively, are 280 miles apart. They start moving toward each other at 3:00PM. At what time and where will they meet?

3) Two motorists start traveling toward each other at 4:30 PM from towns 255 miles apart. If their respective average speeds are 40mph and 45 mph, at what time will they meet?

5)At what rate must Richard travel to overtake KC who is traveling at a rate 20 mph slower if Richard starts 2 hours after KC and wishes to overtake KC in 4 hours?

7)Tom traveled a distance of 265 miles. He drove at 40 mph during the first part of the trip and at 35 mph during the remaining part. If he made the trip in 7 hours, how long did he travel at 40 mph?

9)A boat, propelled to move at 25mph in still water, travels 4.2 miles against the river current in the same time it can travel 5.8 miles with the current. Find the speed of the current.

11) Same and Anne can run around a circular mile in 6 and 10 minutes respectively. If they start at the same instant from the same place, in how many minutes will they pass each other if they run around the track (a) in the same direction? (b)in opposite direction?

13)In 5 hours of flying, a passenger plane is helped by a tall-wind of 50 kph. In the succeeding three hours though, it was lowed down by a 50 kph wind traveling in the opposite direction. If the total distance traveled is 2500 km, how fast is the plane?

15)Pearl and Onyx enter the Pisay Fun Run. Pearl runs at 8 mph and Onyx runs at 6 mph. If they start together, how long will it take before pearl is one-fourth mile ahead of Onyx?

If there are any mistakes, please comment ^_^
If you're having a hard time, consult hanlonmath.com/pdfFiles/314UNIFORMMOTIONPROBLEMS.pdf
But I don't think you'll get much help from that. If you have problems, consult teh mat gawd (AKA Javi) or teh mat goddess (AKA Pia) or look for someone really good at math who you are on friendly terms with.