$($b$)$ Consider a decimal number $-60,$ Find out the equivalent representution and number of digits needed to represent the decimal number in binewy, actal, and hexadecimal representations suituble for modern computers. For example, representing the decimal number $13$ requires $5$ digits in binary $(01101),$ two digits in octal $(15),$ and two digits in hexerdecimal $($OD$).$

$[$Note: Answers written without steps will not be awardid any martes.