Chapter 1, Problem 1.61E

A Toyota Prius Hybrid uses 59.7 L gasoline to drive from San Francisco to Seattle, a distance of 1300 km (two significant digits). (a) What (average) fuel economy, in miles per gallon, did the Prius get during this trip? (b) If gasoline costs $3.90 per gallon, what was the fuel cost for this trip? REGARDING PART B!! So, the answer listed for part b is $62. Why is it 2 significant figures? Shouldn't it be $61.6 since 59.7 L is 3 significant figures?   Here is my calculation:   (59.7 L) x (1.0567 qt/1L) x (1 gal/ 4 qt) = 15.8 gallons x $3.90 = $61.6   I see for part A why it is 2 significant figures, since 1300 km is 2 significant figures, but shouldn't part b be 3 significant figures since the kilometers is not involved?   Thank you!

5) How many minutes is required for sunlight to travel from the Sun to Mars? (Assume the Sun is 1.14 x 10^8 km from Mars and that sunlight travels at 2.99 x 10^5 km/s.)(a) 0.00437 minutes (b) 0.157 minutes(c) 6.35 minutes (d) 381 minutes(e) 22,900 minutes Step by step use the conversion factors with starting point and put lines in between the numbers and cancel the units      6) Platinum is one of the most dense elements (d = 21.5 g/cm^3). What is the volume of a 10.0 g sample of the metal?(a) 0.465 cm^3(b) 2.15 cm^3(c) 21.5 cm^3(d) 215 cm^3(e) 465 cm^3 Step by step, use the conversion factors with starting point and put lines in between the numbers and cancel the units    7) A rare metal alloy is a superconductor at 77 K. What is the temperature in °C ?(a) -350°C (b) -196°C(c) -77°C (d) 196°C(e) 350°C Step by step use the conversion factors with starting point and put lines in between the numbers and cancel the units  8) The average distance from the Earth to the Sun is 1.50 x 10^8km.…

5) How many minutes is required for sunlight to travel from the Sun to Mars? (Assume the Sun is 1.14 x 10^8 km from Mars and that sunlight travels at 2.99 x 10^5 km/s.)(a) 0.00437 minutes (b) 0.157 minutes(c) 6.35 minutes (d) 381 minutes(e) 22,900 minutes Step by step use the conversion factors with starting point and put lines in between the numbers and cancel the units      6) Platinum is one of the most dense elements (d = 21.5 g/cm^3). What is the volume of a 10.0 g sample of the metal?(a) 0.465 cm^3(b) 2.15 cm^3(c) 21.5 cm^3(d) 215 cm^3(e) 465 cm^3 Step by step, use the conversion factors with starting point and put lines in between the numbers and cancel the units    7) A rare metal alloy is a superconductor at 77 K. What is the temperature in °C ?(a) -350°C (b) -196°C(c) -77°C (d) 196°C(e) 350°C Step by step use the conversion factors with starting point and put lines in between the numbers and cancel the units  8) The average distance from the Earth to the Sun is 1.50 x 10^8km.…