Consider the earth and a cloud layer 900 m above the planet

Question

Compute each part of given question:

Question: Consider the Earth and a cloud layer 900 m above the planet to be the plates of a parallel-plate capacitor.

Part A: If the cloud layer has an area of 5.0 km² = 5000000 m², what is the capacitance?

F

Part B: If electric field strength greater than 3.0 x 10⁶ N/C causes the air to break down and conduct charge (lightning), what is the maximum charge the cloud can hold?

C

Please keep it short and simple and please no copy and paste.