Answer:
Subtract 
Step-by-step explanation:
Given

Required
The first step to evaluate the expression
The first step is to evaluate the expression in brackets.
From the question: The expression in bracket is: 
So, the first step is to subtract 
Answer:
t > 8
Step-by-step explanation:
Given that :
Initial volume = 16 litres
Addition rate = 4 litres per minute
Target volume > 48 litres
Let number of minute for which water is added to achieve these = t
Mathematically,
Initial volume + (addition rate * t) > target volume
16 + 4t > 48
Collect like terms
4t > 48 - 16
4t > 32
Divide both sides by 4
4t/4 > 32/4
t > 8
Laura will need add water at 4 Litre per minute rate for more than 8 minutes
Answer:
62.8 units
Step-by-step explanation:
The formula for a cylinder πr²h. R being the radius and h being the height.
Therefore, plug in the numbers and solve.
π(2)²(5) = 20π = 62.8 units
The person on the top is correct good explaining