What is your useing it phone in the night say 2:00amthat when you wake up and put down it phone after using it for a while u say it's about 2:30 in your head and when you look at the time it shocked because the time says 4:00am. how much time did you take to put down your phone ​

a and b sometimes have a positive value

the answer is false. this is because for ice to melt, it requires latent heat of melting. latent heat means heat energy required to change phase without any increase in temperatures. therefore, the ice will take energy from the environment to melt hence atmospheric temperatures will reduce.