Hi, I'm new here, I also don't know if this is in the right section.

I'm not looking for anyone to fully answer this, I just am wondering what do to with it basically. I know the core ideas about exponential graphs, y = yi * (1 + r)^x where yi is initial value and x is time. but its clear that the graph below has to be an inverse. something around the lines of y = (log x)/(log .99) or something...

yea, i'm really lost. my ultimate question is questiong #3 in the picture below,

how would i find an equation or model to represent the two curves below?

Thanks and sorry again if this is in the wrong section.