The answer is the option C and the option D, which are:
C. Double the number of pages in the book.
D. The age of my friend.
The explanation for this problem is shown below:
By definition, a variable is an unkown quantity. In the Option A the quantity is given: 
seconds in a minute. In the option B you know the quantity too, which is 
years old. But the option C and the option D does not give any quantity, you don't know the number of pages in the book or the age of the friend yet. Therefore, the answer is the options C and D.
A = 1/2 (12x² + 8x + 24x + 16)
A = 1/2 (12x² + 32x + 16)
A = 6x² + 16x + 8
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Answer: 6x² + 16x + 8
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Answer:4
Step-by-step explanation:
2x-6=14
2x=8
x=4
(x-p)(x-q)
x^2 -qx -px + pq
x^2 -(q+p) x +pq
so the constant here is the product of p & q
the answer is A
Answer:
1 draw a line of 7.5 cm YZ by scale
2 construct the 90 degree with the help of protecter
3 then cut arc of 6 cm on 90 degree of angle & mark as X
4 join X and Z by scale
