By driving faster
							                                
                                        
                                    
							                        
                    
                            By accelerating gently
							                                
                                        
                                    
							                        
                    
                            By using leaded fuel
							                                
                                        
                                    
							                        
                    
                            By accelerating harshly
							                                
                                        
                                    
							                        
                     
	 
	