Can someone explain to me how to do problems like this?

There are alot of problems in this section at least that have "te^-500t" how do I convert that into something useable?

I get that power is P=VI though how do you calculate the time from that?

Is total power the max power?

Figure 1.5 An ideal basic circuit element. V 1 21.6 The voltage and current at the terminals of the circuit element in Fig. 1.5\";I are zero for t t: I]. For t 13 II], the}: are 11' : 80,000te'm V, t .3 0; ' 15:1250\" A, t :3 0. 21. Find the time when the power delivered to the circuit element is maximum. 1:. Find the maximum value of power. c. Find the total energy delivered to the circuit element. ANSWER: a. 2 m5; '3. 649.6 111W; c. 2.4 m]