When electrical energy is converted into thermal energy, which of the following must be true?

only the amount of electrical energy changes.
only the amount of thermal energy changes.
the total amount of thermal energy plus electrical energy changes.
the total amount of thermal energy plus electrical energy doesn't change.

For the below questions, consider a consumer that consumes two goods, x and z with the following utility function. u with bar on top space equals space x to the power of 1 third end exponent z to the power of 2 over 3 end exponent suppose initial values for income and the prices of goods x and z are y equals 90, p subscript x equals space 10, and p subscript z equals 15 respectively, then the price of good x falls to syntax error from line 1 column 89 to line 1 column 100. unexpected '\'.. what is the magnitude of the total effect