Do you think the changes China underwent in the 20th century have been positive or negative (or both), and how does the film reflect on that question?

uses : -

1.aneroid barometers primarily measure whether pressure is rising or falling.

2.aneroid barometers are often used for reading pressure in homes and recreational boats.  

3.other uses may include barographs in meteorology and altimeters in modern aircraft.  

4.this type of barometer can announce whether a high or low pressure system is coming or whether it is becoming more intense.  

5.there are different types of aneroid barometers, such as the altimeter, which measures altitude, or distance above sea level.  

6.another example is a barograph, which is a modified aneroid barometer that provides constant readings of atmospheric pressure on graph paper.  

7.when used in this capacity, the aneroid barometer can store a week's worth of data.

android diameter a device for measuring atmospheric pressure , often specially calibrated for use as an altimeter ,consisting of a box or chamber partially exhaused of air, having an elastic top and a pointer to indicate the degree of compression of the top caused by the external air

refer to the attachment for the characteristics : -

in an absolute  monarchy, the  monarchrules as an autocrat, with absolutepower  over the state and government — for example, the right to rule by decree, promulgate laws, and impose punishments. the  monarch isnominally sovereign but the electorate, through their legislature, exercise political sovereignty.

explanation:

may i ask what challenges?

chronological thinking is an indispensable tool to structure a historical narrative and to give meaning to a sequence of events. the final section presents the results of a survey to test the chronological thinking of lower secondary school students carried out by the educational research institute.