<image>In order to build a "bookish campus," a school launched a reading month activity and randomly selected some students to record their daily average reading time, $$x$$ (unit: hours). The statistical results are divided into four levels, denoted as $$A$$, $$B$$, $$C$$, and $$D$$, where:
$$A$$: $$0 \leqslant x < 0.5$$,
$$B$$: $$0.5 \leqslant x < 1$$,
$$C$$: $$1 \leqslant x < 1.5$$,
$$D$$: $$1.5 \leqslant x < 2$$.

According to the statistical results, two incomplete charts were drawn as shown in the image.
 
$$(1)$$ The total number of students randomly selected for this statistic is ______; 
$$(2)$$ The central angle of level $$B$$ in the pie chart is ______; 
$$(3)$$ The probability of randomly selecting a student with an "average daily reading time greater than or equal to $$1$$ hour" from the students involved in the statistics is ______; 
$$(4)$$ If the school has $$1200$$ students, estimate the total number of students with an "average daily reading time greater than or equal to $$0.5$$ hours" as ______ students.