The time period of a satellite revolving around earth in a given orbit is \( 7 \ \text{hours} \). If the radius of orbit is increased to three times its previous value, then approximate new time period of the satellite will be:
\( 40 \ \text{hours} \)
\( 36 \ \text{hours} \)
\( 30 \ \text{hours} \)
\( 25 \ \text{hours} \)