A $4m \times 4m$ floor needs to be covered by tiles of size $2m \times 1m$. Two diagonally opposite corners of size $1m \times 1m$ should be left uncovered. How many tiles are required to complete the job without breaking the tiles or overlapping them?
The problem involves covering a 4m x 4m floor with 2m x 1m tiles while leaving two diagonally opposite corners of size 1m x 1m uncovered.

Let's solve this step by step:
Therefore, the correct answer is that it is Impossible to cover the floor with the given conditions.
Let $X(t) =$ number of customers in the system at time $t$ in an $M/M/C$ queueing model, with $C = 3$, arrival rate $\lambda > 0$ and service rate $\mu > 0$. Which of the following is/are true?