Identify the type of study used. A town obtains current employment data by polling 10,000 of its cit izens this month. A) Cross-sectional
B) Prospective
C) Retrospective
D) None of these

A) Cross-sectional

Step-by-step explanation:

A cross-sectional study is a type of study that involves the data i.e. taken from a population for a specific time period.

Here study shows the peoples interest in variables that are be chosen

In the given situation, since a town obtains a data of the current employment for 10,000 of its total citizens

So this represents the cross-sectional

hence, the correct option is A.   Cross-sectional

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

add 8+12 to get a simplified answer of 12r-20