What physical process could geographers track with an arrow on a flow-line thematic map

The point where two air masses meet is called a

Simple astronomical telescope the objective lens has a focal length of 75 cm and that of a piece of 5cm of the lenses are 18 cm apart when will be final image of a distant object before

Look at the data above. provide an explanation for europe’s projected population decrease by the year 2050. (i'm doing this for future kids) the answer is : the percentage of people over the age of 65 and under the age of 15 in europe is currently the same at 16% each. therefore, the majority of the population is between the ages of 16 and 64. in forty years from now, in 2050, a greater percentage of the population will be over the age of 65. europe also has a relatively long life expectancy of 75 years. this, combined with a low birth rate means that by 2050 europe’s population will actually be less than it is today.