[Docs] fix typos on playback readme (#1482)

Signed-off-by: Eric Pan <epan@users.noreply.github.com>

docs/user-guides/h-playback.md

@@ -7,13 +7,13 @@ Follow these steps to create a playback video of an event:
 
 ![select filters](https://d1a3f4spazzrp4.cloudfront.net/kepler.gl/documentation/h-playback-1.png "select filters")
 
-3. Press play to start the video. Click on the  speed value and select/input your desired value _1x_, _2x_, _4x_ on the top right to change the playback speed.
+3. Press play to start the video. Click on the speed value and select/input your desired value _1x_, _2x_, _4x_ on the top right to change the playback speed.
 
 ![change speed](https://d1a3f4spazzrp4.cloudfront.net/kepler.gl/documentation/h-playback-2.gif "select filters")
 
-4. Choose custom y axis. You can click __Select Y Axis__ to change the default distribution graph to a timesieries of selected column. An example use of this function is to show a distance vs. time graph of a given trip.
+4. Choose custom y axis. You can click __Select Y Axis__ to change the default distribution graph to a timeseries of the selected column. An example use of this function is to show a distance vs. time graph of a given trip.
 
-![custome y axis](https://d1a3f4spazzrp4.cloudfront.net/kepler.gl/documentation/h-playback-3.png "select filters")
+![custom y axis](https://d1a3f4spazzrp4.cloudfront.net/kepler.gl/documentation/h-playback-3.png "select filters")
 
 
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