Answer : 4.5 × 10⁴ square inches can be washed per hour.
Step-by-step explanation :
As we are given that an area can be washed at a rate of 4,900 cm²/min. Now we have to determine the square inches can be washed per hour.
Given conversions are:
1 cm = 0.39 in and 1 hr = 60 min
As, 1 cm² = (0.39)² in² and 1 min = 1/60 hr
So, 

Now we have to determine the square inches can be washed per hour.
As, 
So, 
Therefore, 4.5 × 10⁴ square inches can be washed per hour.
2nd one
5th one
are both correct
6126!!!! You are welcome :) I just took this test today
Answer:
Let total students who prefer lemonade is 2a and who prefer ice tea is a.
Students in 6th grade=39
2a+a=39
3a=39
a=39/3
a=13
students who prefer lemonate is 13
and those who prefer ice tea is 2a=26