Question

population pyramids are very useful tools to study population age - sex composition graph can tells us about:
(school aged children vs senior citizen services)
(ie. migration, schools specific to one sex & military bases)
have different impact on shape)
birth rates, death rates, average life, economic development.
reflects natural disaster, wars, political changes and
predicts future population to create urban services like
construction, infrastructure like schools, mass transit etc.

Explanation:

To solve this fill - in - the - blank problem about population pyramids, we analyze each blank based on the knowledge of population pyramids:

First blank (school aged children vs senior citizen services)

Population pyramids show the age - sex structure of a population. The number of school - aged children and senior citizens can be seen from the population pyramid. So this blank is about the age - sex structure (or the distribution of different age groups by sex). We can tell the number of school - aged children (from the younger age groups) and senior citizens (from the older age groups) from the population pyramid, which helps in planning services for them.

Second blank (migration, schools specific to one sex & military bases)

These factors (migration, single - sex schools, military bases) affect the sex ratio and the population distribution by sex and age. So this blank is about factors that affect the population's sex - age composition. Migration can change the number of people of different sexes and ages in an area. Single - sex schools and military bases can also impact the local sex - age population structure.

Third blank (have different impact on shape)

Birth rates, death rates, and average life expectancy have different impacts on the shape of the population pyramid. For example, high birth rates and low death rates lead to a broad - based (pyramid - shaped) population pyramid, while low birth rates and low death rates with high life expectancy lead to a more rectangular or even inverted - pyramid - shaped population pyramid. So this blank is about how these demographic indicators (birth rates, death rates, average life expectancy) influence the shape of the population pyramid.

Fourth blank (birth rates, death rates, average life ____, economic development)

The correct term here is "expectancy". So the full phrase is "birth rates, death rates, average life expectancy, economic development". Average life expectancy is an important demographic measure that, along with birth rates, death rates, and economic development, affects the population structure.

Fifth blank (reflects natural disaster, wars, political changes and ____)

These events (natural disasters, wars, political changes) and other events like economic crises or pandemics can affect the population (through changes in birth, death, or migration rates). So this blank can be filled with "other major events (or similar terms like social upheavals)".

Sixth blank (predicts future population ____ to create urban services like construction, infrastructure like schools, mass transit etc.)

Population pyramids help in predicting the future population trends (such as growth, decline, or changes in age - sex structure). This prediction is useful for planning urban services and infrastructure. If we know the future population trends (for example, if the population of school - aged children is going to increase, we need to plan more schools), we can create appropriate urban services.

Final Answers for each blank:

1. Age - sex structure (or distribution of age groups by sex)
2. Factors affecting sex - age composition
3. Influence the shape of the population pyramid
4. Expectancy
5. Other major events (e.g., economic crises, pandemics)
6. Trends

Answer:

To solve this fill - in - the - blank problem about population pyramids, we analyze each blank based on the knowledge of population pyramids:

First blank (school aged children vs senior citizen services)

Population pyramids show the age - sex structure of a population. The number of school - aged children and senior citizens can be seen from the population pyramid. So this blank is about the age - sex structure (or the distribution of different age groups by sex). We can tell the number of school - aged children (from the younger age groups) and senior citizens (from the older age groups) from the population pyramid, which helps in planning services for them.

Second blank (migration, schools specific to one sex & military bases)

These factors (migration, single - sex schools, military bases) affect the sex ratio and the population distribution by sex and age. So this blank is about factors that affect the population's sex - age composition. Migration can change the number of people of different sexes and ages in an area. Single - sex schools and military bases can also impact the local sex - age population structure.

Third blank (have different impact on shape)

Birth rates, death rates, and average life expectancy have different impacts on the shape of the population pyramid. For example, high birth rates and low death rates lead to a broad - based (pyramid - shaped) population pyramid, while low birth rates and low death rates with high life expectancy lead to a more rectangular or even inverted - pyramid - shaped population pyramid. So this blank is about how these demographic indicators (birth rates, death rates, average life expectancy) influence the shape of the population pyramid.

Fourth blank (birth rates, death rates, average life ____, economic development)

The correct term here is "expectancy". So the full phrase is "birth rates, death rates, average life expectancy, economic development". Average life expectancy is an important demographic measure that, along with birth rates, death rates, and economic development, affects the population structure.

Fifth blank (reflects natural disaster, wars, political changes and ____)

These events (natural disasters, wars, political changes) and other events like economic crises or pandemics can affect the population (through changes in birth, death, or migration rates). So this blank can be filled with "other major events (or similar terms like social upheavals)".

Sixth blank (predicts future population ____ to create urban services like construction, infrastructure like schools, mass transit etc.)

Population pyramids help in predicting the future population trends (such as growth, decline, or changes in age - sex structure). This prediction is useful for planning urban services and infrastructure. If we know the future population trends (for example, if the population of school - aged children is going to increase, we need to plan more schools), we can create appropriate urban services.

Final Answers for each blank:

1. Age - sex structure (or distribution of age groups by sex)
2. Factors affecting sex - age composition
3. Influence the shape of the population pyramid
4. Expectancy
5. Other major events (e.g., economic crises, pandemics)
6. Trends