These steps are involved in the production of work by a four-stroke heat engine. Place the steps in the correct order. Piston moves up, compressing gas and causing gas to increase its temperature: Piston moves up, pushing burned gases through exhaust valve: 1 Spark plug fires, causing combustion as gas is still compressed; increase in energy from combustion pushes piston down: Piston moves down, allowing fuel-air mixture to enter intake valve:

You have two photos of a person walking. one shows the person at the corner of third and main streets, the other shows the person at the corner of tenth and main streets. there are lampposts at every corner in this town, and the first picture shows it to be 10: 32: 00 exactly. the second picture shows it to be 10: 49: 30. you know three facts: (1) all of the clocks are synchronized; (2) there are exactly 12 equal-sized blocks per kilometer in this town; and (3) the streets that cross main in this area are numbered consecutively, with no interruptions. what is the person’s average speed in kilometers per hour?