Answer: The spring of the spring is 25 N/m.
Explanation:
Mass of the body = 25 g= 0.025 kg (1 kg = 1000 g)
Oscillation is 4 sec = 20
Oscillation in 1 sec =
Frequency of the vibration of the spring = 
Force constant can be calculated bu using the relation between the frequency and, mass and spring constant 'k'



The spring of the spring is 25 N/m.
We need the frequency of the photon, it is v = c/ λ
Where c is 3 x 10^8 ms^-1 and λ
is the wave length
We also need the expression of
connecting frequency to energy of photon
which is E = hv where h is Planck’s
constant
Combining the two equations
will give us:
E = h x c/λ
Inserting the values, we will
have:
E = 6.626 x 10^-34 x 3 x 10^8 /
0.126
E = 1.578 x 10^ -24 J
The random variable in this experiment is a Continuous random variable.
Option D
<u>Explanation</u>:
The continuous random variable is random variable where the data can take infinite variables. For example random variable is taken for measuring "speed of automobiles" on the highways. The radar instrument depicts time taken by automobile in particular what speed. They are the generalization of discrete random variables not the real numbers as a random data is created. It gives infinite sets of all possible outcomes. It is obvious that outcomes of the instrument depend on some "physical variables" those are not predictable as depends on the situation.