Find the amount of work that the spring does. This can be found using the equation 1/2kx^2. Then, you must set that equal to the amount of kinetic energy the car has. This is possible thanks to the work-energy theorem.
1/2kx^2 = 1/2mv^2
Solve to find velocity. Remember, the spring is displaced .15 m, not 15!
To find the acceleration, use F = ma. The force being applied to the car is kx, and you know the mass. You do the math.
For problem C I don't know, haven't done that yet in my class. Sorry!
The answer is A. Photosynthesis is caused when plants trap light energy in their leaves and use that energy to change water and carbon dioxide into glucose. Hope this helps :)
The correct answer would be the sun
1790 = electrical energy / 2940 seconds
Electrical energy = 5262.6kJ
or
1.79kW X 49/60
= 1.46kWh
