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:
Step 1: Using the given condition that each frequency is \( \sqrt[12]{2} \) times the frequency of the previous note.
The ratio of the frequencies of any two notes can be expressed as:
\[ \text{Frequency ratio} = \left( \sqrt[12]{2} \right)^n \] where \( n \) is the number of steps between the two notes.
Step 2: Finding the ratio of frequencies of F\# and C.
Since F# is 6 steps away from C in the sequence, we have:
\[ \text{Ratio of frequencies of F\# and C} = \left( \sqrt[12]{2} \right)^6 = \sqrt{2}. \]
In the given figure, PQRS is a parallelogram with PS = 7 cm, PT = 4 cm and PV = 5 cm. What is the length of RS in cm? (The diagram is representative.)
A line of symmetry is defined as a line that divides a figure into two parts in a way such that each part is a mirror image of the other part about that line.
The given figure consists of 16 unit squares arranged as shown. In addition to the three black squares, what is the minimum number of squares that must be coloured black, such that both $PQ$ and $MN$ form lines of symmetry? (The figure is representative) 

The reflectance geometry of white-sky albedo can be represented as __________
Clouds appear white in optical visible spectral bands of remote sensing images due to _________ scattering.
If the emissivity of an object varies with wavelength, it is called as __________