Calculation of Surface Area:
Given:
Area of the metal plate = 450 cm^2

The metal plate has two sides, so the total surface area is double the given area.
Total surface area = 2 * 450 cm^2 = 900 cm^2

Calculation of Volume:
Given:
Thickness of Cu to be deposited = 0.004 cm

Volume of the Cu layer can be calculated using the formula:
Volume = Area * Thickness

Volume = 900 cm^2 * 0.004 cm = 3.6 cm^3

Calculation of Mass of Cu:
Given:
Density of Cu = 9 g/cm^3

Mass can be calculated using the formula:
Mass = Volume * Density

Mass = 3.6 cm^3 * 9 g/cm^3 = 32.4 g

Calculation of Time:
Given:
Current = 9.5 A
Charge of Cu = 0.00033 g/C

Charge can be calculated using the formula:
Charge = Current * Time

Time can be calculated using the formula:
Time = Mass of Cu / (Charge of Cu * Current)

Time = 32.4 g / (0.00033 g/C * 9.5 A)

Simplifying the equation:
Time = 32.4 g / (0.003135 g/A)

Time = 10339.26 seconds (rounded to 2 decimal places)

Explanation:
To deposit a copper layer of 0.004 cm in thickness on both sides of a metal plate with an area of 450 cm^2, we need to calculate the time required.

First, we calculate the total surface area of the metal plate, which is double the given area. Then, using the thickness of the copper layer, we calculate the volume of copper to be deposited.

Next, we calculate the mass of copper using the density of copper. By multiplying the volume with the density, we get the mass of copper required.

Finally, we use the given current and the charge of copper to calculate the time required to deposit the desired amount of copper. By dividing the mass of copper by the product of the charge of copper and the current, we obtain the time in seconds.

In this case, the calculated time is approximately 10339.26 seconds.