Answer:
The answer is choice (3)
Explanation: Land materials do require more energy than water to raise their temperature by one degree, hence why water gets heated a lot easier than something like wood.
Total distance = 76+54 = 130km
total time = 2+5 = 7hrs
Av. speed = 130/7 = 18.571km/hr = 18.6 km/h ( 3 sig fig)
The correct answer is Mechanics
Potential Energy = mass * 9.81 * height
(9.81 is the acceleration due to gravity on Earth)
PE = 6 * 9.81 * 6 = 353.16 J
