Which if statements are not valid; that is, will cause Python to display a syntax error message? (Assume variables a and b have been initialized.) Select one or more: if (a > b): print ("Hello") if a > b: print ("Hello") if (a > b) print ("Hello") if a > b: print ("Hello") A code fragment should print "The temperature is pleasant" if the temperature assigned to degrees C is between 15 and 25 degrees, or "The temperature is cold" is the temperature is below 15 degrees. Select the code fragments that do this. Select one: if degrees C = 15: print ('The temperature is pleasant') if degrees C = 15: if degrees C