A sheet of paper is folded along the white dotted lines and then cut along black dotted lines as depicted below. Out of the four scaled down options, which is the CORRECT resultant unfolded paper? 
A
B
C
D
Shown on the left is a set of equations. Which option belongs to the same set? 
Shown below is an arrangement of closely stacked spheres. Assume each one to be in contact with its immediate neighbour. What is the total number of points where the spheres touch each other?
The 12 musical notes are given as \( C, C^\#, D, D^\#, E, F, F^\#, G, G^\#, A, A^\#, B \). Frequency of each note is \( \sqrt[12]{2} \) times the frequency of the previous note. If the frequency of the note C is 130.8 Hz, then the ratio of frequencies of notes F# and C is:

