DU A dog is running in a straight line to catch a ball. Its motion is shown on the following
graph of horizontal
position vs. time t.

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

c)as speed changes, wavelength and frequency change.

everything changes!

heat the gas and measure the pressure