Power Systems
In hydroelectric power plants

 both operating and initial cost are high.
 operating cost is high and initial cost is low.
 both operating and initial cost are low.
  operating cost is low and initial cost is high.

ANSWER DOWNLOAD EXAMIANS APP

Power Systems
Critical mass is

  minimum mass of fissionable material required to sustain chain reaction.
 none of these.
 maximum mass of fissionable material required to sustain a chain reaction.
 a mass of fissionable material required to stop a chain reaction.

ANSWER DOWNLOAD EXAMIANS APP