function buyLandETH_amount(uint8 _level, uint8 _star) public pure returns(uint){

         
        if(_level <= 1){
    	   return  0.2 ether * 2**(uint(_star)-1) ;
    	} 
    	else if(_level > 1) {    
    	   return  0.2 ether * 2**(uint(_star)-1)*(3**(uint(_level)-1))/(2**(uint(_level)-1)) ;
    	} 
    }