<span>Answer:
Using 1/f = 1/d' + 1/d ...(where d' object distance and d is image distance)
1/4 = 1/7 + 1/d
1/4 - 1/7 = 1/d
3/28 = 1/d
d = 28/3
d = 9.33 cm</span>
Neptune would have a slower orbit i just did this
Answer:
550000000N/m
Explanation:
Given that a copper wire has a radius of 2.9 mm. When forces of a certain equal magnitude but opposite directions are applied to the ends of the wire, the wire stretches by 5.0×10−3 of its original length.
Original length L = 0.005L
the strain = extension/ original length
the strain = 0.005L / L
the strain = 0.005
Young modulus = stress / strain
11 × 10^10 = stress / 0.005
Cross multiply
Stress = 11 × 10^10 × 0.005
Stress = 550 000000 N/m
Therefore, the tensile stress on the wire is 550000000 N/m.

Actually Welcome to the Concept of the Kinematics.
1.) Distance travelled = 15+20 = 35 miles.
Ai the total distance covered is 35 miles.
2.) Displacement is the shortest distance from the initial point to the final point.
here it's ==> 20-15 = 5 miles
hence, displacement = 5 miles