Answer A is correct - m1l
The Doppler effect is the term that best describes the change in frequency of waves when there is motion between the source of the waves and the observer. The correct option among all the options that are given in the question is the first option or option "a". I hope the answer helps you.
Answer:
-0.4D(maybe)
Explanation:
combined focal length (f)= 0.4m
D1 = 5D
Then f1= 1/D1
= 1/5 = 0.2 m
1/f=1/f1+1/f2
1/0.4=1/0.2+1/f2
f2= -5/2
D2=1/f2= -0.4D
What happens to water when it becomes ice? Answer: the water level does NOT change even if it does melt, deposition is the term used when water liquid becomes solid ice, and also the water molecules DECREASE/LOWER speed and join in straight positions. 2) Answer: Conductors of both electrical and heat.