The United States of America, due to its immense size and diverse heritage, has one of the most complex cultural identities in the world. Millions of immigrants from all over the globe have journeyed to America (26) the Europeans discovered and colonised the land back in the 17th and 18th centuries. The blending of cultural (27) and ethnicities in America led to the country becoming known as a “melting pot.” As the third largest country in both area and population, America’s size has enabled the formation of subcultures within the country. These subcultures are often geographical as a result of settlement (28) by non-natives as well as regional weather and landscape differences. While there are countless ways to divide the U.S. into regions, here we have referenced the four regions that are West, Midwest, North East and South. People from (29) region may have different lifestyles, cultural values, business practices and dialects. While there are qualities and values (30) most Americans commonly share, it is important not to generalise or assume that all Americans think or act the same way.

GIRLS' EDUCATION

Improving girls' educational levels has been demonstrated to have clear impacts on the health and economic future of young women, which in turn improves the prospect of their entire community. Research shows that every extra year of school for girls increases their lifetime income by 15%. Improving female education, and thus the earning potential of women improves the standard of living for their own children.

Yet, many barriers to education for girls remain. In some African countries, such as Burkina Faso, girls are unlikely to attend school for such basic reasons as a lack of private toilet facilities for girls. Higher attendance rates of high schools and university education among women, particularly in developing countries, have helped them make inroads into professional careers with better-paying salaries and wages.

Education increases a woman's (and her partner's and the family's) level of health and health awareness. Furthering women's levels of education and advanced training also tends to lead to later ages of initiation of sexual activity, later ages at first marriage, and later ages at first childbirth, as well as an increased likelihood to remain single, have no children, or have no formal marriage and alternatively, have increasing levels of long-term partnerships. It can lead to higher rates of barrier and chemical contraceptive use (and a lower level of sexually transmitted infections among women and their partners and children), and can increase the level of resources available to women who divorce or are in a situation of domestic violence. It has been shown, in addition, to increase women's communication with their partners and their employers, and to improve rates of civic participation such as voting or the holding of office.

In science, a theory is a reasonable explanation of observed events that are related. A theory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of this is found in the kinetic molecular theory, in which gases are pictured as being made up of many small particles that are in constant motion.

A useful theory, in addition to explaining past observations, helps to predict events that have not as yet been observed. After a theory has been publicized, scientists design experiments to test the theory. If observations confirm the scientists' predictions, the theory is supported. If observations do not confirm the predictions, the scientists must search further. There may be a fault in the experiment, or the theory may have to be revised or rejected.

Science involves imagination and creative thinking as well as collecting information and performing experiments. Facts by themselves are not science. As the mathematician Jules Henri Poincare said: "Science is built with facts just as a house is built with bricks, but a collection of facts cannot be called science any more than a pile of bricks can be called a house."

Most scientists start an investigation by finding out what other scientists have learned about a particular problem. After known facts have been gathered, the scientist comes to the part of the investigation that requires considerable imagination. Possible solutions to the problem are formulated. These possible solutions are called hypotheses. In a way, any hypothesis is a leap into the unknown. It extends the scientist's thinking beyond the known facts. The scientist plans experiments, performs calculations and makes observations to test hypotheses. For without hypotheses, further investigation lacks purpose and direction. When hypotheses are confirmed, they are incorporated into theories.