Answer:
Vivian should start working by 10.25 am.
Step-by-step explanation:
Time taken to mow the lawn = 1 hour and 10 minutes
Time to trim bushes = 30 minutes
Time for putting down mulch = 35 minutes
Time to get dressed = 20 minutes.
Total time = 1 hour + (10+30+35+20) minutes
= 1 hour + 95 minutes
= 1 hour + (60+35) minutes
= 1 hour + 1 hour + 35 minutes
= 2 hours 35 minutes.
This means Vivian should start working 2 hours 35 minutes before 1:00 pm.
So, it becomes ; 10:25 am.