Answer:
the minimum length of the first piece is 4 feet
You earn $15 per lawn. 1 lawn would be $15. 15(1) is 15.
7 lawns would be 15(7), which is 105.
Answer: Option 'D' is correct.
Step-by-step explanation:
Since we have given that
Upper P (Upper B vertical line Upper A)
means

It means that probability of getting event B given that Event A is occurred.
D. The probability of event B occurring, given that event A has already occurred. is also expressed as 
Hence, Option 'D' is correct.
Qty · % = Total
Drink 1: x .25 = .25x
Drink 2: 15 - x .10 = .10(15 - x)
Mixture: 15 .21 = .25x + .10(15 - x)
(15)(.21) = .25x + 1.5 - .10x
3.15 = .15x + 1.5
1.65 = .15x
11 = x
Drink 1 (25%) is 11 liters
Drink 2 (10%) is 15 - 11 = 4 liters