Answer:
In mathematics, the empty set is the unique set having no elements; its size or cardinality (count of elements in a set) is zero.
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Step-by-step explanation:
Your answer would be
70a + 21b
Answer:
When number of bricks is multiplied by 2, the length is multiplied by
B) 2
Step-by-step explanation:
Number of bricks is two times the length of the wall
i.e. Number of bricks= 2×Length of the wall
When the number of bricks is multiplied by 2, the length is also multiplied by 2
since, when number of bricks=6 then, length of wall=3
and when number of bricks=2×6=12 then, length of wall=2×3=6
Hence, when number of bricks is multiplied by 2, the length is multiplied by
B) 2
Recall that

is only defined for

, and under this condition we have that

. But 1.7 > 1, so

is not a real number.