Hi there, I've been struggling very much with this differential equation and I would really appreciate if someone could help me out. Thanks!

Question 4. A patch of moss initially occupies an area of 20 square centimetres. The moss grows at a rate inversely proportional to the size of the patch. After 250 hours, the patch has grown to 30 square centimetres.

a) Find the size of the patch as a function of time (in hours).

b) How large is the patch after 300 hours?

c) How long does it take until the moss reaches 50 square centimetres? (a)