The population in the united states in 2015 was 321 million people. it is projected to increase to 438 million people by the year 2050.

if projections are true, the us population will increase % from 2015 to 2050.

So, en 2015 the population is 321 mill, and the prediction is it will increase to 438 mill in 2050.

If the projection is true, we can see that the relation between these numbers is 438/321 = 1.364

this means that the population in 2050 is 1.364 times the population in 2015. In percentage, the population in 2050 is 136.4% of the population in 2015, so the increment in population is 36.4%.

graph slopes whilst gas cools, then it is flat whilst conensation to liquid happens, the coolong liquid then graphs as a slope when it solidifies graph is flat

latent heat