How many calories are released when 500 g of water cools from 95.0°c to 25.0°c?

                  35,000 cal  will released.

Explanation:

By definition 1 kcal (=1000 calorie) is the approximate amount of energy released when the temperature of 1.000 kg of water is lowered by 1.000 °C (at a pressure of one atm.). It is about 4.2 kJ of energy.

                                   q = mC∆T

where q = heat (calories);      m = mass (500g);        C = specific heat (1 cal/g/deg);           ∆T = change in temp.                                                                                                    Thus,

              q = (500 g)(1 cal/g/deg)(95-25) = (500)(1)(70) = 35,000 cal

a police officer and a ambulance

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current