3. A block starting from rest slides down the length of an 18 m plank with a uniform acceleration of 4.0 m/s2. How long does the block take to reach the bottom?​

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 !

Looking at this barometer, is the air pressure high or low? what type of weather would you expect? high, bad low, bad high, good low, good

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?