Finding an exponential function given its graph

Lessons

1. Determine an exponential function in the form $y=a \cdot b^x$ with the given graph.
   
   
2. Determine an exponential function in the form ${y = 3^{x-h} + k }$ with y-intercept 5 and asymptote ${y = -4.}$
3. Determine an exponential function in the form $y=a \cdot 2^{bx}+k$ with the given graph.