Answer:
Sam is providing the biggest power i.e. 50 W
Step-by-step explanation:
Sam is moving house and is carrying a 300N box of books up a flight of steps 5m high, it takes her 30 seconds.
Sam's power :
![P_1=(W_1)/(t_1)\\\\P_1=(F_1d)/(t_1)\\\\P_1=(300* 5)/(30)\\\\P_1=50\ W](https://img.qammunity.org/2022/formulas/physics/high-school/olmvw4fzhgeo7bzu3u74ceoj53kg7b7rdk.png)
Gary follows her carrying a bag of clothes doing 1000 J of work; it only takes him 25 seconds.
Gary's power :
![P_2=(W_2)/(t_2)\\\\P_2=(1000)/(25)\\\\P_2=40\ W](https://img.qammunity.org/2022/formulas/physics/high-school/1mt770la10cddcx66y47xz66c5dge429bo.png)
So, it is clear that Sam is providing the biggest power.