3. A uniform metre rule is balanced at the 50 cm mark. Weights of 1.5 N and
3.0 N are hung from the 10 cm and 40 cm marks respectively, as shown in Fig. 2.1.
10 cm
40 cm 50 cm
80 cm
1.5N
3.ON
w
Fig. 2.1
A weight Whanging from the 80 cm mark balances the system.
Calculate
(a) the moment about the 50 cm mark of the 1.5N weight,

b. latent learning (the word "latent" itself means something that exists but isn't obvious, only under certain conditions! )

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.

i think the answer would be b