A train is 1000 meters long. It is travelling at a constant speed, and approaches a tunnel that is 3000 meters long. From the time that the last car on the train has completely entered the tunnel until the time when the front of the train emerges from the other end, 30 seconds pass. Determine the speed of the train, in kilometres per hour.

The numbers on a football field indicate 10 yard increments. you walk around the perimeter of a football field between the pylons. you walk a distance of 30623 yards. find the area and perimeter of the indicated regions. write your answers as mixed numbers, if necessary. a. one end zone: perimeter: yd area: yd2 b. the playing field (not including end zones): perimeter: yd area: yd2 c. the playing field (including end zones): perimeter: yd area: yd2

Find the power set of each of these sets, where a and b are distinct elements. a) {a} b) {a, b} c) {1, 2, 3, 4} show steps

Two cities a and b are 1400km apart and lie on the same n-s line. the latitude of city a is 23 degrees. what is the latitude of city b. the radius of the earth is approximately 6400km.