Answer:
![9.3\cdot 10^(37)](https://img.qammunity.org/2020/formulas/physics/middle-school/4wtkp67orj5h839g5qimambbv7e5x72ws3.png)
Step-by-step explanation:
Power is defined as the energy produced (E) per unit of time (t):
![P= (E)/(t)](https://img.qammunity.org/2020/formulas/physics/middle-school/9jvlkz3b74pq6w8n59r6mm4pz2vqlzadlt.png)
This means that the energy produced in the Sun each second (1 s), given the power
, is
![E=Pt=(4.0\cdot 10^(26)W)(1s )=4.0\cdot 10^(26) J](https://img.qammunity.org/2020/formulas/physics/middle-school/u1ez8mgkvjyo9rad8t1wmkj6trxtiu24cl.png)
Each p-p chain reaction produces an amount of energy of
![E_1 = 4.3\cdot 10^(-12) J](https://img.qammunity.org/2020/formulas/physics/middle-school/gtsh07ipb41myqbluw0xkk2yd6svrtzohs.png)
in order to get the total number of p-p chain reactions per second, we need to divide the total energy produced per second by the energy produced by each reaction:
![n=(E)/(E_1)=(4.0\cdot 10^(26) J)/(4.3\cdot 10^(-12) J)=9.3\cdot 10^(37)](https://img.qammunity.org/2020/formulas/physics/middle-school/m69006xoo5x82bnxx9jw2271cmaldgd5ns.png)