A wire has J = (-2.7i + 5k) A/m² and A = (40i + 72j + 30k) cm² , where i, j, and k are to imply the x, y, and z directions respectively.

What is the z component of the wire's cross sectional area?

Do not include units on numerical answers. If your answer is in scientific notation, use a capital E to represent x10^ , for example: 4.8x10^-2N would be typed as 4.8E-2 instead.

The z component of the wire's cross-sectional area is 30 (in cm²) or 30E-2  (in m²). 

(please answer after knowing the acceptable unit)

Step-by-step explanation

Here J represents the current density or the current in the unit area of the wire and A represents the cross-section area of the wire.

Now, A=(40i+72j?+30k) cm2

Then, the z component of the wire's cross-sectional area is 30 (in cm²) or 30E-2  (in m²). 

If they want the answer in the CGS unit system, or in cm², then your answer will be 30, and if they want the answer in the SI unit system, or in m², then your answer will be 30E-2.