"They have learned the precise depths where the boundaries between the earth's layers are located" is the one among the following choices given in the question that scientists have <span>learned from studying seismic waves that travel through earth’s interior. The correct option among all the options given is option "B". </span>
Protective Factors is the term taken.
Let distance be x.
Time in going, t 1 = x/50
Time in coming, t 2 = x/40
Total time T = x/40 +x/50 = 9x/200
Average speed = total distance/ total time
=( x+x)/(9x/200)= 2x ×200/9x = 400/9 = 44.44 km/h
Answer:
The spring stretched by x = 13.7 cm
Explanation:
Given data
Mass = 3 kg
k = 120 
Angle
= 34°
From the free body diagram
Force acting on the box = mg sin
⇒ F = 3 × 9.81 × 
⇒ F = 16.45 N ------- (1)
Since box is attached with the spring so a spring force also acts on the box.
= k x
= 120
-------- (2)
The net force acting on the body is given by
Since acceleration of the box is zero so



Put the values from equation (1) & (2) we get
16.45 = 120
x = 0.137 m
x = 13.7 cm
Therefore the spring stretched by x = 13.7 cm