Part a
Answer: 17.58 km/h

Total Distance =10 km
Total time =0.5689 h

Part b
Answer: 17.626 km/h

Total Distance =42.195 km
Total time =2.3939 h

If the object is kept in between the principle axis and the focus but some what nearer to the focus then we will get the enlarge,erect,and real image.
Answer:
C
Explanation:
When A and B come in contact with each other, +12 - 12 = 0 so their changes cancel.
Now C has a charge of +12
When A and C come together they each have an equal share of that 12, so each of them has 6
So the answer is
A B C
6 0 6
which is C
Applicable linear expansion equation:
ΔL = αΔTL
In which
ΔL = change in length, α = Linear expansion coefficient of steel, ΔT = change in temperature, L = original length
Therefore,
ΔL = 12*10^-6*(18.5-(-3))*1410 = 0.36378 m