Assume that x is a variable that has been declared as a double and been given a value. write an expression to compute the quartic root of x. the quartic root of a number is the square root of its square root. examples: for example, the quartic root of 16.0 is 2.0 because: the square root of 16.0 is 4.0 and the square root of 4.0 is 2.0. another example: the quartic root of 81.0 is 3.0 because the square root of 81.0 is 9.0 and the square root of 9.0 is 3.0. thus, to find the quartic root of a number you take the square root of the number and then take the square root of that. in this exercise you must find the quartic root of x in a single expression-- you must not write any statements. also, you may only use the sqrt() function-- no other functions. (hint: you will need to call the sqrt() function twice-- and you will need to pass the return value of one of those calls as argument to the other call. and remember: write an expression, not a statement.)