Final answer:
Measurement units vary across different countries, leading to difficulties in communication, trade, and scientific research. Efforts have been made to promote uniformity in measurement units, such as the International System of Units (SI).
Step-by-step explanation:
Difference in Measurement Units and Difficulties Faced
Measurement units vary across different countries, leading to difficulties in communication, trade, and scientific research. For example, one country may use the metric system while another uses the customary system. This can result in misunderstandings and errors when comparing measurements and making conversions.
Efforts to Bring Uniformity
To address these difficulties, efforts have been made to promote uniformity in measurement units. The International System of Units (SI) is a globally accepted system that provides standard units for length, mass, time, and other physical quantities. Organizations such as the International Bureau of Weights and Measures work to maintain and improve the SI system, ensuring consistency and compatibility across countries.