Final answer:
The true statements are: B. The expression 50 + 40h + 80 + 30h is the total cost for the project. E. Zen Garden is cheaper if the job is 2 hours.
Step-by-step explanation:
To determine which statements are true, let's analyze each option:
A. The expression 80h represents the total charge for Zen Garden to visit. This statement is false because the expression 80h only represents the cost per hour for Zen Garden, not the total charge for the visit.
B. The expression 50 + 40h + 80 + 30h is the total cost for the project. This statement is true, as it accurately represents the total cost for the project, including the initial charges and hourly rates for both Zen Garden and Potted Plant.
C. If Bob hires Zen Garden for 3 hours, the total charge will be $170. This statement is false. To calculate the total charge if Bob hires Zen Garden for 3 hours, we need to use the expression 50 + (40*3) = $170.
D. The expression 80 + 30h represents the total charge for Potted Plant to complete the job. This statement is false because the expression 80 + 30h represents the cost per hour for Potted Plant, not the total charge to complete the job.
E. Zen Garden is cheaper if the job is 2 hours. This statement is true. If we calculate the total charge for Zen Garden for 2 hours using the expression 50 + (40*2) = $130, it is lower than the total charge for Potted Plant, which would be 80 + (30*2) = $140.
Therefore, the true statements are B and E.