If total output in an economy is $600,000 and the total work-hours in the economy are 40,000, labor productivity is:

$15 per hour

Explanation:

Labor productivity is defined as the number of goods and services produced by workers in an organization at a given point in time.

The formular for labor productivity is

= Output ÷ total work hour

= $600,000 ÷ 40,000

= $15

Therefore, labor productivity is $15 per hour

the first successful, urban blues recording, selling more than 75,000 copies, was made in year 1920.

mamie smith recorded the first commercially successful example of the urban blues,   with the recording of “crazy blues”."crazy blues" was recorded on august 10, 1920, in new york city. within a month of the release of “crazy blues” it had sold 75,000 copies.