What is 29.6 divided by 3.7

The exact slope is impossible to know for sure, because the function is not written out explicitly. (If we did, we could just do dV/dt evaluated at t = 10.)

However, you can estimate the slope at P by finding the average rate of change between t=5 and t=15, or by taking the average of the slopes of the adjacent secants. There are several ways to approximate the answer, but I don’t think you can find its exact value.