The atomic number is 13, so there are 13 electrons.

$1s$, $2s$, $2p$, $3s$, $3p$. $1s^2 2s^2 2p^6 3s^2 3p^1$ $\boxed{\text{}1s^2 2s^2 2p^6 3s^2 3p^1\text{}}$

• B) Atomic number = 20

$1s$, $2s$, $2p$, $3s$, $3p$, $4s$. $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2$ $\boxed{\text{}1s^2 2s^2 2p^6 3s^2 3p^6 4s^2\text{}}$

• C) Atomic number = 19

$1s$, $2s$, $2p$, $3s$, $3p$, $4s$. $1s^2 2s^2 2p^6 3s^2 3p^6 4s^1$ $\boxed{\text{}1s^2 2s^2 2p^6 3s^2 3p^6 4s^1\text{}}$

• D) Atomic number = 1

$$
1s^1
$$
$$
\boxed{\text{}1s^1\text{}}
$$

• E) Atomic number = 7

$1s$, $2s$, $2p$. $1s^2 2s^2 2p^3$ $\boxed{\text{}1s^2 2s^2 2p^3\text{}}$

• F) Atomic number = (unclear) The atomic number for element F is unclear in the image (both "10" and "7" are crossed out). Therefore, the electron configuration cannot be determined.

• G) Atomic number = 10

$1s$, $2s$, $2p$. $1s^2 2s^2 2p^6$ $\boxed{\text{}1s^2 2s^2 2p^6\text{}}$

• H) Atomic number = (missing) The atomic number for element H is missing in the image. Therefore, the electron configuration cannot be determined.

• I) Atomic number = (missing) The atomic number for element I is missing in the image. Therefore, the electron configuration cannot be determined.

• J) Atomic number = 5

$1s$, $2s$, $2p$. $1s^2 2s^2 2p^1$ $\boxed{\text{}1s^2 2s^2 2p^1\text{}}$

• K) Atomic number = 17

$1s$, $2s$, $2p$, $3s$, $3p$. $1s^2 2s^2 2p^6 3s^2 3p^5$ $\boxed{\text{}1s^2 2s^2 2p^6 3s^2 3p^5\text{}}$