To find percent error you use the following formula:

% error = (1.6 - 1.9)/1.9 * 100% = 15.79%
The answer you are looking for is B. 70.69
Subtract 20 and 10. To get your answer
Answer:
Option A is correct.
Step-by-step explanation:
The height of the rectangular pack is h1 = 4r
The height of the parallelogram = 2r + the height of equilateral triangles with a side of 2r
The height of equilateral triangle with a side of 2r = (side)/2*√3
=(2r)/2 *√3 = r√3
The height of the parallelogram h2 = 2r+r√3 = r(2+√3)
So,the ratio of h1 to h2 is :
4r : r(2 +√3)
Cancelling r we get
Hence, the ratio is 4 : 2 +√3
Adds 3 each time
first term is 5
an=a1+d(n-1)
d=common difference
a1=first term
an=5+3(n-1)
18th term
a18=5+3(18-1)
a18=5+3(17)
a18=5+51
a18=56
C is answer