ANSWER PART D ONLY

To print one thousand textbooks, two production machines work on the task. Working alone, the rst machine would take or hours or the second machine would take a hours. a. What expression represents the portion of the task done by the rst machine each hour? In. What expression represents the portion of the task done by the second machine each hour? c. Write a single fraction that represents the portion of the task completed each hour if both machines work together. cl. If a is 3 hours and b is 10 hours. how long does it take the two machines to do the job when working together