0.616 is the distance from the top
of the building to the top of the window.
Answer:
1. telescope
2.

f- focal length
f- focal length r- the radius of curvature of the mirror

p-the distance of the object from the vertex of the mirror
l-the distance of the figure from the vertex of the mirror
Answer:
Here Strain due to testing is greater than the strain due to yielding that is why computation of load is not possible.
Explanation:
Given that
Yield strength ,Sy= 240 MPa
Tensile strength = 310 MPa
Elastic modulus ,E= 110 GPa
L=380 mm
ΔL = 1.9 mm
Lets find strain:
Case 1 :
Strain due to elongation (testing)
ε = ΔL/L
ε = 1.9/380
ε = 0.005
Case 2 :
Strain due to yielding


ε '=0.0021
Here Strain due to testing is greater than the strain due to yielding that is why computation of load is not possible.
For computation of load strain due to testing should be less than the strain due to yielding.
-di represents an image in front of a lens