Answer:
the speed of the car at the top of the vertical loop 
the magnitude of the normal force acting on the car at the top of the vertical loop 
Explanation:
Using the law of conservation of energy ;


The magnitude of the normal force acting on the car at the top of the vertical loop can be calculated as:
![F_{N} = \frac{mv^2_{top}}{R} \ - mg\\\\F_{N} = \frac{m(2.0 \sqrt{gR})^2}{R} \ - mg\\\\F_{N} = [(2.0^2-1]mg\\\\F_{N} = [(2.0)^2 -1) (50*10^{-3} \ kg)(9.8 \ m/s^2]\\\\](https://tex.z-dn.net/?f=F_%7BN%7D%20%3D%20%5Cfrac%7Bmv%5E2_%7Btop%7D%7D%7BR%7D%20%5C%20-%20mg%5C%5C%5C%5CF_%7BN%7D%20%3D%20%5Cfrac%7Bm%282.0%20%5Csqrt%7BgR%7D%29%5E2%7D%7BR%7D%20%5C%20-%20mg%5C%5C%5C%5CF_%7BN%7D%20%3D%20%5B%282.0%5E2-1%5Dmg%5C%5C%5C%5CF_%7BN%7D%20%3D%20%5B%282.0%29%5E2%20-1%29%20%2850%2A10%5E%7B-3%7D%20%5C%20kg%29%289.8%20%5C%20m%2Fs%5E2%5D%5C%5C%5C%5C)

If the shopping cart is parallel to the ground, the weight is acting vertically downward, then force is equal to weight. The normal force will be acting perpendicular to the ground,and acting upward opposite of the weight.
Electron is a fundamental Particle by JJ Thomson so it was truly difficult to say that electron is a negative charge
Speed of an object is kinetic energy
The step missing is after the number 4. Because, after the antenna captures de modultates waves, it has to be demodulated in order to be able to the signal be heard, seen or used.
So, the answer is that waves are demodulated and it before the signal is heard, seen or used.