How many observations have x$1$ values greater than $30?$

Simultaneously sort x$1,$ then x$2,$ and then x$3$ all in ascending order. After the variables have been sorted, what is the first observation for x$1,$ x$2,$ and x$3?$

Simultaneously sort x$1$ and then x$2$ in descending order and then x$3$ in ascending order. After the variables have been sorted, what is the first observation for x$1,$ x$2,$ and x$3?$

How many missing values are there in x$1,$ x$2,$ and x$3?$