The file extension for access 2007 and 2010 database filenames is .accdb. what is the file extension for older versions of access database files.

The earlier file format was the .mdb file format. If a person has a file that is stored in the .mdb format and gets a new version of Access or needs an upgrade, he or she may choose not to upgrade due to the fact that he or she will not be able to make design changes to the .mdb file.

answer: when the substance contain the two parts (polar and non-polar) like soap.

explanation:

soap is produced from the basic hydrolysis of ester "saponification", it is considered as a salt of hydrocarbons. the soap molecule contains the two parts: a polar group   (-coo-na+) and a non-polar group (r-hydrocarbon part). the polar group is called the head and the tail is the non-polar group. the polar group is hydrophilic in nature (water loving) and the non-polar group is hydrophobic in nature (water repelling).the polar/non-polar nature of a substance is useful that it can dissolve the non-polar substances by the polar part and also can dissolve the polar substances by the non-polar part. it commonly used in detergents and soaps.