Design of external rear-view mirrors on cars have been streamlined from flat, circular discs to a rounded hemisphere in order to reduce drag coefficient and improve fuel economy. calculate the annualized amount of fuel in liters and money in usd saved by the rounded design as compared to an older flat design. assume mileage of 24,000 km/yr, with mean speed of 95 km/hr, engine efficiency is 0.30, energy value of gasoline is 44,000 kj/kg, density of gasoline is 0.75 kg/l, density of air is 1.20 kg/m3 and cost of fuel is $0.90 /l

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?