Which parts of an electric generator are connected?
a. two brushes
b. two slip rings
c. the armature and axle
d. the armature and commutator

D. the armature and commutator            

Explanation:

An electric generator is based on the principle that when a conducting coil rotates in the magnetic field, an electric current is generated.  It converts mechanical energy to electrical energy.

Armature is the rotating part of the generator. Armature is connected to commutator which is a cylindrical in shape and rotates with it. It also connects the armature to the external circuit by brushes.  

i think it because equal matrices have equal dimensions, only square matrices can be symmetric. for all indices and . every square diagonal matrix is symmetric, since all off-diagonal elements are zero. in linear algebra, a real symmetric matrix represents a self-adjoint operator over a real inner product space.

volts times amps 6 x 0.5 3w