Answer:
Explanation:
Given
Sphere of Radius R
Suppose mass of block is m
At any instant \theta Normal reaction(N) and weight(mg) is acting such that
, where v is velocity of block at any angle \theta
When block is just about to leave then N=0
therefore

-------------------1
Also by conserving Energy we get
Potential Energy=kinetic Energy of block

here h=vertical distance traveled by block
From diagram



-----------------2
From 1 and 2



Thus from this value of h is



Answer: only the third option. [Vector A] dot [vector B + vector C]
The dot between the vectors mean that the operation to perform is the "scalar product", alson known as "dot product".
This operation is only defined between two vectors, not one scalar and one vector.
When you perform, in the first option, the dot product of any ot the first and the second vectors you get a scalar, then you cannot make the dot product of this result with the third vector.
For the second option, when you perform the dot product of vectar B with vector C you get a scalar, then you cannot make the dot product ot this result with the vector A.
The third option indicates that you sum the vectors B and C, whose result is a vector and later you make the dot product of this resulting vector with the vector A. Operation valid.
The fourth option indicates the dot product of a scalar with the vector A, which we already explained that is not defined.
To solve this problem it is necessary to apply the concepts related to wavelength as a function of frequency and speed, as well as to determine the wavelength as a function of length.
From the harmonic vibration generated we know that the total length of the string will be equivalent to a half of the wavelength, that is

Where,
Wavelength
Therefore the wavelength for us would be,

From the relationship of speed, frequency and wavelength we know that



Therefore the speed of the wave is 232.75m/s
Breathing is called respiration.