Imagine I merge the two datasets below using the following code

use test$\_$score.dta, clear

merge $1$:$1$ student using hw$\_$score.dta, keep$(3)$ nogen

How many observations will remain in the dataset after the code above is execut

$\backslash$table$[[,$student,test$\_$score,student,hw$\_$score,$],[1,1,82,1,2,99],[2,2,74,2,3,82],[3,3,93,3,4,83],[4,4,91,4,5,90],[5,5,91,5,6,70]]$