What is the weight of a 9.8 kg object on planet Earth?

the second one and the forth one are in the purple because they are opinions and the rest are in the yellow

explanation:

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue

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.