4) Consider fusion reactor based on inertial confinement concept. It uses solid D-T target (50%T+50%D) with the mass density p=0.2 g/cm3 and the radius of R=0.5 mm. Find how many targets per second, N4, should be ignited to produce electric power Pe=300 MW if the efficiency of the conversion of the heat to electricity is n = 30%. Assume that each fusion D+T reaction gives EDT=17.5 MeV of energy and D-T fuel burns down completely. (20 points)