1. Determine the rule of an exponential function that has the given properties. Validate your answer using a graph.

a) Has a base of 6, an asymptote at y= -7, has a parameter k = +/- 1, and passes through the coordinate points (3, -4) and (4, 11).

b) Has an initial value of 4893, passes through the coordinate point (-2, 93) and has a range of {y|y > -7, yER}

c) Has a range if {y|y < 0, yER}, has a base of 2, has no horizontal translation from the base function, and passes through the coordinate points (0, -37.6) and (7, -75.2).