What is the act of arranging elements to form design​

This measure is supposed to equal six beats. in one or two sentences, explain how you can add one note and one rest to complete this measure. assume that one quarter note equals one beat.

1× 10×10×10+2×30×30=[tex]1 \times 10(4) + 2 \times 10(3) = \\ [/tex]

During which century can it be inferred that "the masque of the red death" probably occurred?