Chi ti?t D?ch v? in tem nhãn m? ph?m ?em l?i s? ?n t??ng cho th??ng hi?u D?ch v? in tem nhãn m? ph?m ?em l?i s? ?n t??ng cho th??ng Hello?uThe graphic can be manipulated by changing the voltage on the gun to accelerate or reduce the velocity of electrons along with modifying the electromagnetic wavelength by using the solenoids.Nh? s? d?ng công