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M2 Mei energy and power question

Hi guys,
I'm completely stuck on this question:

A conveyor belt picks up stationary saks of grain (mass 25kg) and delivers them to a place 5m higher with speed 1.5ms^-1 . The sacks are delivered at the rate of 1 sack/ 6 seconds.
i) calculate the total mechanical energy given to one sack by the conveyor belt
ii) calculate the average power with which the conveyor belt is working, assuming friction may be ignored.

THe back of the book gives the answers as 1250J and 209W, but I can't work out where this is from (also, being MEI, they might just be wrong...)

for i) I got 1225 (5*9.8*25)- the only thing I can think of is that maybe i should be using g=10, rather than 9.8, but the rest of the questions in the exercise all use 9.8. AM I missing another factor?

for ii) I got 367.5 (1.5*25*9.8).

Any help would be much appreciated!