1. Q: For the 200-meter race, the end and start of the runway are all in a straight line. Because the semi-circular runway is bypassed in the middle, the starting point of the outer runway should be moved forward. If each runway is 1.2 meters wide, how many meters should the starting point of the outer runway move forward? (accurate to 0. 1 m)

2. Q: The radius of the inner ring of a ring is 7cm, and the width of the ring is 2cm. Find the area of the ring.

3. Q: It takes 0. 1 cm to saw a 36.9 cm long piece of wood into 3.9 cm and 6.9 cm pieces. How many pieces can these two specifications saw to minimize waste?

4. Q: The number of natural numbers between 1 and 1994 that are not divisible by 5, 6 and 7.

5. Q: If a car travels from A to B, it can arrive 1 hour in advance if its speed is increased by 20%; If you drive at the original speed of 200 kilometers per hour and increase the speed by 25%, you can arrive at 12 in advance. How many kilometers is the difference between A and B?

6. Q: If a commodity is sold at a 20% discount, it can still make a 20% profit. What is the expected profit at the time of pricing?

7. Q: A water conservancy project can be completed by unit A alone for 63 days and then by unit B alone for 28 days. It takes 48 days for the two teams to cooperate to complete the task. First, unit A did it alone for 42 days, and then unit B continued to do it. A * * *, how many days does it take?

8。 Q: The diesel fuel carried on board can be used for up to 6 hours, and it is downwind when leaving, with a speed of 30 kilometers per hour; When driving back, against the wind, 24 kilometers per hour. How many kilometers should a ship travel in the opposite direction at most?

9. Q: 50 people from Class 6 of Hongxing Primary School (1) went for a spring outing 52 kilometers away. Now there is only 1 car and only 25 passengers. It is known that the speed of a car is 40 kilometers per hour and the walking speed of a person is 4 kilometers per hour. Then, after reasonable arrangements, all the students can get to the spring outing place as soon as possible.

10. q: two cars, a and b, leave from a and b respectively at the same time, and the directions are opposite. The two cars met for the first time at a distance of 60 kilometers. After meeting, the two cars continued to drive at the original speed and immediately returned along the original road after reaching the starting point of the other side. On the way, the two cars met for the second time at a distance of 40 kilometers. Q: What is the distance between A and B?