Friends tell you that on a recent trip their average velocity was +20 m/s. Is it possible that at any time during their trip their velocity was -20 m/s? Explain, and give an example to justify your answer. PLEASE HELP

Yes. Please find the answer in the explanation.

Explanation:

Yes. Since velocity is a vector quantity, that is, it has both magnitude and direction.

If the displacements covered are not of the same direction, the velocity will not also of the same direction.

Take for instance, if the velocity in a positive is 40 m/s and velocity in the opposite direction is - 20 m/s . Then, the resultant velocity will be 40 - 20 = 20 m/s

Therefore,  it is possible that at any time during their trip their velocity was -20 m/s.

-first use of geothermal energy occurred more than 10,000 years ago in north america by american paleo-indians

-the first industrial use of geothermal energy began near pisa, italy in late 18th century

-in 1904, italian scientist piero ginori conti invented the first geothermal electric power plant in which steam was used to generate the power

-with the above experiment, the first geothermal plant in usa started in 1922 with a capacity of 250 kilowatts

-however, in 1946 first ground-source geothermal heat pump installed at commonwealth building in portland, oregon

-during the 1960’s, pacific gas and electric began operation of first large scale geothermal power plant in san francisco, producing 11 megawatts

-in 1973, when oil crisis began many countries began looking for renewable energy sources and by 1980’s geothermal heat pumps (ghp) started gaining popularity in order to reduce heating and cooling costs

-as effect of climate change started showing results, governments of various countries joined hands to fight against it, for which kyoto protocol was signed in japan in 1997, laid out emission targets for rich countries and required that they transfer funds and technology to developing countries, 184 countries have ratified it

hope this