$1.$ Convert octal number $725\mathrm{.}6$ to binary number; convert hexadecimal number $2$F$.$D to binary number.

$2.$ Problem $1\mathrm{.}10($b$)$ from the textbook $($derive two digits after the radix point in the hexadecimal number$).$

$3.$ Problem $1\mathrm{.}16($b$)$ from the textbook $($derive two digits after the radix point in the octal number$).$

$4.$ Carry out the following additions and subtractions in binary representation:

a$)10000011+01011001$;

b$)10000011-01011001$;

c$)11110011+10011110$;

d$)11110011-10011110$

$5.$ Add $7$AD$2$ and $1493$ in hexadecimal format; Subtract $413$ by $237$ in octal format.