A mixed cost contains a variable element and a fixed element.
Option a
<u>Explanation:</u>
Mixed costs are those costs that has both variable and fixed component. Example: operating cost of a machinery includes fixed costs that cannot be changed with other variable costs like fuel, insurance, depreciation, etc.
It is also named as semi-variable costs. And the formula to calculate mixed cost is as follows,

where,
- y is the "total cost
"
- a is the "fixed cost per period"
- b is the "variable rate per unit of activity"
- x is the "number of units of activity"
This question involves the concepts of dynamic pressure, volume flow rate, and flow speed.
It will take "5.1 hours" to fill the pool.
First, we will use the formula for the dynamic pressure to find out the flow speed of water:

where,
v = flow speed = ?
P = Dynamic Pressure = 55 psi
= 379212 Pa
= density of water = 1000 kg/m³
Therefore,

v = 27.54 m/s
Now, we will use the formula for volume flow rate of water coming from the hose to find out the time taken by the pool to be filled:

where,
t = time to fill the pool = ?
A = Area of the mouth of hose =
= 1.98 x 10⁻⁴ m²
V = Volume of the pool = (Area of pool)(depth of pool) = A(1.524 m)
V =
= 100.1 m³
Therefore,

<u>t = 18353.5 s = 305.9 min = 5.1 hours</u>
Learn more about dynamic pressure here:
brainly.com/question/13155610?referrer=searchResults
Answer:
i think it is iron
Explanation:
its the only one that makes sense to me
Trick question? In order to have kinetic energy, an object must be moving. Therefore, in this case, kinetic energy would be 0. If it were asking about potential energy, it would be a different story.