The molecules of ice stick together in the process of cohesion. They are tightly packed so there isn't much room to move. Liquid water is a looser hold. The molecules can go past one another, and they will take the shape of whatever container they occupy. Water vapor is loosely contained, and it will will fill whatever container it is kept in, and it will take its shape, too.
So power is considered as the rate of doing work. Base on the problem given, my analysis is that the machine who finish the work faster is machine C. Therefore, in order to finish the same amount of work in a short period of time you are going to expend the most power. My answer is Machine C.
Average speed = (total distance covered) / (time to cover the distance)
Ian's total distance = (2km + 0.5km + 2.5km) = 5 km
Ian's total time = 3 hours
Average speed = (5km) / (3 hours)
Average speed = 1.66 km/hr
I think it is June. June is the longest day/
Liar, not even 40 points....