A biologist places a colony consisting of 5000 bacteria into a petri dish. After the initial placement of the bacteria at time t=0, the biologist measures and estimates the number of bacteria present every half hour. This data was then fitted by an exponential curve of the form \(y=c\cdot 2^{kt}\) where c and k are constants, t is measured in hours, and y is measured in thousands of bacteria. The scatterplot together with the exponential curve are shown below.

According to the scatterplot, the biologist's measurements indicate that the number of bacteria present quadrupled in 6 hours, and the exponential curve passes through the corresponding data point at time t=6. The exponential function also agrees with the initial number of bacteria. What is the value of ck ?