Answer: The answer that I got was J.
Look at the picture. I have no idea why I can't add an answer.
The easy answer: If, say, B is the zero matrix, i.e.

then

Answer:
Step-by-step explanation:
1 hour=60 min
7 hours=60×7=420 min
number of blink=420×13=5460
If a quadrilateral is a rhombus then:
i) all its sides have equal length,
and
ii) the 2 diagonals are perpendicular and bisect each other.
The 2 diagonals of rhombus JKLM intersect at N.
Then m(MNJ)=90°, |JN|=4 and |NM|=3 units
thus, by the Pythagorean theorem,

The perimeter of the rhombus is 4*5 units=20 units.
Answer: 20 units