Answer: 40 J
Explanation: Work is equal to the product of force and distance.
W = Fd
= 4N ( 10 m)
= 40 J
Answer:
E. Coefficient of linear expansion
Answer:

Explanation:
Frequency of each electromagnetic wave is same thus we can interfere them along X axis in Phase diagram.
In phase diagram indicate each wave as vector with amplitude as length and phase difference as angle. (shown in attachment)
Now take component of E2 and E3 amplitude along X direction.
Net amplitude of all E in X direction =
+ cos(45)[
+
]
⇒
Final resultant have no change in frequency
So , resultant is 
It would be autotroph and hetrotroph