Pria's radio produces 80 useful energy units for every 100 units of electricity used. the efficiency of the radio is 0.80 percent 20 percent 80 percent 100 percent

The efficiency of the radio is 80 percent.

80 useful energy units

100 units of electricity used

80 ÷ 100 =  0,8 × 100 = 80%

answer; the president uses mass media to gain support for policies;

answer; to save lives and protect property;