The echo is weaker than the original sound since the echo has a smaller amplitude than the original sound because sound spreads and its intensity decreases with distance. For example, when the sound from a speaker is heard and is compared to its echo, the echo heard has a lower amplitude than the actual sound.
Answer:
63°
that's my answer
but then I am sorry if I'm wrong
Explanation:
90-27 = 63°

Diameter of objective lens = 1.22m
Wavelength of light = 4000Å
We have to find resolving power of telescope ..
★ Resolving power of telescope is given by
RP = D/1.22λ
- D denotes diameter of lens
- λ denotes wavelength of light
RP = D/1.22λ
RP = (1.22×10⁷)/(1.22×4)
RP = 0.25 × 10⁷
RP = 2.5 × 10⁶
★ Resolving power of microscope is given by
RP = 2μsinθ/λ
Amplitude, is the answer to the question