img fixedsize 
<img src="fixedsize.svg">
<img width="50" height="25" src="fixedsize.svg">
<img width="100" height="25" src="fixedsize.svg"><br>
obj fixedsize
<object data="fixedsize.svg"></object>
<object width="50" height="25" data="fixedsize.svg"></object>
<object width="100" height="25" data="fixedsize.svg"></object><br>
embed fixedsize
<embed src="fixedsize.svg">
<embed width="50" height="25" src="fixedsize.svg">
<embed width="100" height="25" src="fixedsize.svg"><br>
inline fixedsize
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     width="100" height="50" version="1.1">
<rect x="0" y="0" width="100" height="50" fill="black"/>
<circle cx="50" cy="25" r="30" fill="gray"/>
</svg>
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     width="50" height="25" version="1.1">
<rect x="0" y="0" width="100" height="50" fill="black"/>
<circle cx="50" cy="25" r="30" fill="gray"/>
</svg>
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     width="50" height="25" overflow="visible" version="1.1">
<rect x="0" y="0" width="100" height="50" fill="black"/>
<circle cx="50" cy="25" r="30" fill="gray"/>
</svg>
<br>
img contained
<img src="contained.svg">
<img width="50" height="25" src="contained.svg">
<img width="100" height="25" src="contained.svg"><br>

obj contained
<object data="contained.svg"></object>
<object width="50" height="25" data="contained.svg"></object>
<object width="100" height="25" data="contained.svg"></object><br>

img standalone
<img src="standalone.svg">
<img width="50" height="25" src="standalone.svg">
<img width="100" height="25" src="standalone.svg"><br>

obj standalone
<object data="standalone.svg"></object>
<object width="50" height="25" data="standalone.svg"></object>
<object width="100" height="25" data="standalone.svg"></object><br>

<img width="200" height="auto" src="test.svg" style="border: solid red">
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     style="border: solid red" 
     width="100%" height="100%"
     viewBox="0 0 100 50" 
     version="1.1">
<rect x="0" y="0" width="100" height="50" fill="black"/>
<circle cx="50" cy="25" r="30" fill="gray"/>
</svg>
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink"
     style="border: solid red; width: 100%; height; 100%" 
     viewBox="0 0 100 50" 
     version="1.1">
<rect x="0" y="0" width="100" height="50" fill="black"/>
<circle cx="50" cy="25" r="30" fill="gray"/>
</svg>

<iframe width="50" height="50" src="standalone.svg"></iframe>