You have also the total power generated is 200W
To figure out the kind of exercises, you need to master the definition of each unit. for example
power: watt (W) is
joule/secWork: is Newton. meter =
Joule
To obtain the work done by the adult, we have to convert the power (watt) into a work by multiplying by the time (

* seconds = Joule)
10 minutes is 60 * 10 =
600 seconds200Watt * 600 second = 120000 joules =
120 Kj
So the work is 120Kj