Keiko builds a transformer in the lab, but it does not decrease the voltage as much as she needs. what should keiko change to further reduce the voltage? she should make the number of coils in the primary winding less than in the secondary winding. she should make the number of coils in the primary winding the same as in the secondary winding. she should increase the number of coils in the secondary winding. she should increase the number of coils in the primary winding.