The binary equivalent of the decimal number $4.625$ is:

To convert the decimal number $4.625$ into its binary equivalent, we separate the integer part and the fractional part:
1. **Integer Part ($4$):**
Dividing by 2 repeatedly:

* $\frac{4}{2}=2$ with a remainder of $0$
* $\frac{2}{2}=1$ with a remainder of $0$
* $\frac{1}{2}=0$ with a remainder of $1$
Reading the remainders from bottom to top gives $(4{)}_{10}=(100{)}_2$.

2. **Fractional Part ($0.625$):**
Multiplying by 2 repeatedly and noting down the integer components:

* $0.625\times 2=1.25$ (Integer part is $1$)
* $0.25\times 2=0.50$ (Integer part is $0$)
* $0.50\times 2=1.00$ (Integer part is $1$)
Reading the integer parts from top to bottom gives $(0.625{)}_{10}=(0.101{)}_2$.

Combining both components results in $100.101$, which is represented in the options with a hyphen as 100-101.