Answer:
![E = 1.95 * 10^(-4) J](https://img.qammunity.org/2020/formulas/physics/high-school/sn3fbe5yh9rdgbrokat2rv8pnkd4azd8z7.png)
Step-by-step explanation:
As we know that the mass of the fleas is given as
![m = 3.9 * 10^(-4) kg](https://img.qammunity.org/2020/formulas/physics/high-school/hkrp5pf5kt8s8rfjc9slp73qcukb6e82yp.png)
now the speed of the fleas is given as
![v = 1 m/s](https://img.qammunity.org/2020/formulas/physics/middle-school/pocbtb5zm2jqghn4kcam6yoiqpzppd1cv7.png)
now just before it will jump let say it has some energy E
so as per energy conservation law we can say that this total initial energy will convert into its kinetic energy just after the jump
so the initial total energy is given as
![E = (1)/(2)mv^2](https://img.qammunity.org/2020/formulas/physics/high-school/a6v945qd41emef6onxg3p5f2tnzsqhd1k6.png)
![E = (1)/(2)(3.9 * 10^(-4))(1^2)](https://img.qammunity.org/2020/formulas/physics/high-school/nk8uo6pvjfb3bv3zyo7q989adelgv724av.png)
![E = 1.95 * 10^(-4) J](https://img.qammunity.org/2020/formulas/physics/high-school/sn3fbe5yh9rdgbrokat2rv8pnkd4azd8z7.png)