What is the primary determinant of the voltage developed by a battery?

The seven sisters, seven stars located more than 400 light-years away in the taurus constellation can be seen here with venus and another constellation, orion. the seven stars stay grouped together but seem to move, like the planet venus. why do stars seem to move like planets in the night sky?

When doing scientific research ,the sources used should be ?

Difference between natural and artifical magnet