input: Write a python function to perform a binary search on a 2D array to find a key in the first column.
  assert binarySearch2D([[1, 5, 8], [2, 15, 20], [3, 25, 30], [11, 13, 16]], 3) == True
  assert binarySearch2D([[1, 5, 8], [2, 15, 20], [3, 25, 30], [11, 13, 16]], 11) == True
  assert binarySearch2D([[1, 5, 8], [2, 15, 20], [3, 25, 30], [11, 13, 16]], 5) == False
output: def binarySearch2D(matrix, key):
      low, high = 0, len(matrix) - 1
  
      while low <= high:
          mid = (low + high) // 2
          if matrix[mid][0] == key:
              return True
          elif matrix[mid][0] < key:
              low = mid + 1
          else:
              high = mid - 1
  
      return False