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Answer:
D)378kJ
Explanation:
Applying,
E = F×d................ Equation 1
Where E = Energy expanded by the car, F = Wind resistance, d = distance
From the question,
F = 0.42v²............ Equation 2
Susbtitute equation 2 into equation 1
E = 0.42v²d.............. Equation 3
Given: v = 30 m/s, d = 1 km = 1000 m
Substitute these values into equation 3
E = 0.42(30²)(1000)
E = 378000
E = 378 kJ
Hence the right option is D)378kJ