Table 1: border=1 cellspacing=0 cellpadding=0
    
Table 2: border=1 cellspacing=1 cellpadding=0
    
Table 3: border=1 cellspacing=0 cellpadding=1
    
Table 4: border=1 cellspacing=1 cellpadding=1
    
Same tables as above but removing height="50%" from the second row:
Table 5: border=1 cellspacing=0 cellpadding=0
    
Table 6: border=1 cellspacing=1 cellpadding=0
    
Table 7: border=1 cellspacing=0 cellpadding=1
    
Table 8: border=1 cellspacing=1 cellpadding=1