The Decay Factor of an Exponential Function $P ( t )$

Multiple Choice

The decay factor of an exponential function $P ( t )$ is 0.61. The initial value is 1.48. Then a formula for P is

A) $P = 0.61 \times t ^ { 1.48 }$
B) $P = 0.61 \times 1.48 ^ { t }$
C) $P = 1.48 \times t ^ { 0.61 }$
D) $P = 1.48 \times 0.61 ^ { t }$