The following procedure was intended to remove all occurrences of element x from list l. explain why it doesn't always work and suggest a way to repair the procedure so that it performs its intended task.

procedure delete (x: elementtype; var l: list);
var
p: position;
begin
p: = first(l);
while p < > end(l) do begin
if retrieve(p, l) =x then
delete(p, l);
p : = next(p, l)
end
end; { delete }

Convert and simplify the following sentences to conjunctive normal form (cnf): (a) (p → (q → r)) → (p → (r → q)) (b) (p ∧ q) → (¬p ↔ q) (c) ((p → q) ∧ ¬q) → ¬p

Michael has written an e-mail to his employees that describes a new product special that will be introduced to the customers next week. by taking time to make sure the e-mail is well written, logical, and organized, michael has made sure his message has the characteristics of a) effective communicationb) ineffective communicationc) barriers to communicationd) workplace communication

Write a program that displays the following menu: geometry calculator 1. calculate the area of a circle 2. calculate the area of a rectangle 3. calculate the area of a triangle 4. quit enter your choice (1-4): if the user enters 1, the program should ask for the radius of the circle and then display its area. use the following formula: area = ď€(the square of r) use 3.14159 for ď€ and the radius of the circle for r. if the user enters 2, the program should ask for the length and width of the rectangle and then display the rectangle’s area. use the following formula: area = length * width if the user enters 3, the program should ask for the length of the triangle’s base and its height, and then display its area. use the following formula: area = base * height * .5 if the user enters 4, the program should end. input validation: display an error message if the user enters a number outside the range of 1 through 4 when selecting an item from the menu. do not accept negative values for the circle’s radius, the rectangle’s length or width, or the triangle’s base or height. note: if the user enters an improper menu choice (1-4), the program prints "the valid choices are 1 through 4. run the program again and select one of those." if the user enters a negative radius, the program prints "the radius can not be less than zero." if the user enters a negative value for height or base, the program prints "only enter positive values for base and height."