Three people pull simultaneously on a stubborn donkey. jack pulls directly ahead of the donkey witha force of 97.3 n, jill pulls with 60.9 n in a direction 45° to the left, and jane pulls in a direction 45 to the right with 159 n. (since the donkey is involved with such uncoordinated people, who can blame it for being stubbon? ) find the magnitude of the net force the people exert on the donkey. number what is the direction of the net force? express this as the angle from straight ahead between 0° and 90° with a positive sign for angles to the left and a negative sign for angles to the right.

tube or goog with be a great resource to with that question

-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

myth. it was once thought that animals, including cats and dogs, could only see in black and white. however, scientists have proven this to be a myth. in all animals, including humans, the perception of colour is determined by the presence of cells in the eye called cone photoreceptors.