Problem 1: Consider the following ambiguous BNF grammar: → ? : | = → && | || | ! | | true 0 false | () → x y z Rewrite the grammar so that it is no longer ambiguous and has the following properties: The operators have the following precedence, from highest to lowest: ( ), !, &&, 11, ?:, =. The !, ?:, and = operators are right associative, and the && and || operators are left associative

Liquid flows at steady state at a rate of 2 lb/'s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. the liquid specific enthalpy at the inlet is 40.09 btu/lb and at the exit is 40.94 btub. the pump requires 3 btu/s of power to operate. if kinetic energy effects are negligible and gravitational acceleration is 32.174 tt/s, the heat transfer rate associated with this steady state process is most closely 1)-2,02 btu/s from the liquid to the surroundings 2)-3.98 btu/s from the surroundings to the liquid. 3)-4.96 btu/s from the surroundings to the liquid. 4)-1.04 btu/s from the liquid to the surroundings.