Sit-ups, Lunges

At Lynette's gym
35 sit-ups
Walking lunges holding a 10kg dumbell overhead (in both hands)

Don't know if this is an AMRAP or a RFT.
I wanted to do 5 rounds and made 4.
I wanted to cap it at 15 minutes and got stubborn and didn't want to break the last round, so finished in 16:30
Lunging distance was length of the gym and back which took me 11 or 12 lunges each time, so guessing about 25m round trip.
I usually do these sorts of lunges with a barbell and thought holding the shorter dumbell would require me to use much less weight. 10kg was too light really.