2a for example the first one,2sec. You know that every second it moves 3metres further. So 2x3=6 but you start at 0.50m so 6+0.50=6.5
D) waves are used to transmit the rail signal though the air. these waves are encoded at different frequencies for different stations
Ok I know this from other stuff potassium nitrate would completely dissolve in a 100 g on was at 30 c would be 60 but this is 40 so I’m not really sure and I don’t what to ok give you a bad grade but if I had to guess I would go with 65 grams