Answer:
If it is triple it means we multiply it by 3 then it is 36.3 m/s/s
Answer:

Explanation:
given,
refractive index of lens, n = 1.70
Radius of curvature of front surface. R₁ = 20 cm
Radius of curvature of the back surface, R₂ = 30 cm
focal length= ?

R₁ = +20 cm
R₂ = -30 cm
n = 1.70




the focal length of the lens is equal to 17.15 cm
This actually means that the object which is emitting light spectrum is moving away from us.. how do you know that ? well.. it is clearly mentioned that it is a red shift so the wavelengths will stretched more . and thus the spectrum turns more reddish as it has higher wavelengths .. hence so called red shifts