$1.(20\text{'})$ Convert the following numbers between different number systems. Clearly show your steps for the data conversion.

$.$ Evaluate the decimal equivalent for integer binary number: ${10110110}_2.$

$.$ Convert the decimal number $145\mathrm{.}26$ to its equivalent binary form. $($Note: For the fraction part, you just need to keep first $4$ digits.$)$

$.$ Convert the binary number ${11000111100100010101110}_2$ to hexadecimal form.

$.$ Convert decimal number ${2189}_{10}$ to hexadecimal form.