650 kgs is equal to 1,433 lbs. I believe the mistake would be that they forgot to add a period in between 65 and the 0, because 65.0 kgs is equal to 143.3 lbs.
Divide 5.6 by 8 which is 0.7. Since the image of the ant is 8 times bigger we need to divide by 8 to make it actual size.
The ant's actual length is 0.7 cm.
The third one, for every 6 french fries, there is 1 packet of ketchup.