Answer:
16 J
Explanation:
It is given that,
Work done, W = 2 J
A spring is stretched by 2.0 cm from its equilibrium length
We need to find how much more work will be required to stretch it an additional 4.0 cm.
Let k is the spring constant of the spring. When W = 2J, and x = 2 cm, then energy required to stretch the spring is :

The energy required to stretch the spring from 2 cm to additional 4 cm i.e. 2+4= 6 cm.

So, the required work done is 16 J.
The ability of singers to shatter glass is due to the control of frequency in their voices. The sound waves will vibrate the air particles that surround the glass at its resonant frequency. The glass will break if a singer sings too loudly.
Well i had the same question on my test, and when the graph in 2.5 seconds goes up from the equilibrium it reaches a positive maximum, so that would be your answer.
b. positive maximum
The source on the nagnetic field on the ssun is the moons pull