What factors depends on whether or not a driver can divide attention between two tasks ?
Attention can never be divided into two tasks .
The more similar the sources of information are or the more concentration they require, the easier it will be for you to attend to them .
The more different the sources of information are (following a vehicle with your eyes and listening to a passenger) or the less concentration they require (such as music on the radio), the easier it will be to attend to them .