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a train travels 78 kilometers in 4 hours, and then 94 kilometers in 1 hours. what is its average speed?

my answer is 34.4 km/hr
is this correct?

Agas initially at p1 = 1 bar and occupying a volume of 0.5 liter is compressed within a piston–cylinder assembly to a final pressure p2 = 4 bar. (a) if the relationship between pressure and volume during the compression is pv = constant, determine the volume, in liters, at a pressure of 3 bar. (b) repeat for a linear pressure–volume relationship between the same end states. reference

Do you agree with scientist’s prediction about the warming of alaska and other polar regions?

Can anybody me with this? ? (picture included.)