Answer:
Answer is
By topic, By collection.
Refer below.
Explanation:
Quick SearchLinks to an external site. lets you refine or narrow your search results using links on the right side of the screen. Do a search on wind power. Some criteria that can refine your search results in Quick Search are:
By topic
By collection
<em><u>Answer</u></em>
5 hours
<em><u>Explanation</u></em>
The two working together can finish a job in

Also, working alone, one machine would take one hour longer than the other to complete the same job.
Let the slower machine working alone take x hours. Then the faster machine takes x-1 hours to complete the same task working alone.
Their combined rate in terms of x is

This should be equal to 20/9 hours.

Multiply through by;





Factor to get:


It is not feasible for the slower machine to complete the work alone in 4/9 hours if the two will finish in 20/9 hours.
Therefore the slower finish in 5 hours.