To melt tin taken at 15 degrees, 600g of kerosene was burned. Determine the mass of tin if at each time only half of the energy released by burning kerosene was transferred to tin. pls help❤️

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

What equation is used to calculate the weight of an object on a plant ?

If you let go of the notebook after lifting it, will it move? how?