Can i use multi mediaCodecs in same type

mediasoup libraries
1 
    router: {
        mediaCodecs: [
		{
            kind: 'audio',
            mimeType: 'audio/opus',
            clockRate: 48000,
            channels: 2
	    },{
            kind: 'audio',
            mimeType: 'audio/PCMA',
            preferredPayloadType: 8,
            clockRate: 8000,
            rtcpFeedback: [{
                type: 'transport-cc'
            }]
        }]
    },

In example I used two mediaCodecs in same type audio. Is this correct?

2

Yes, it is.

3

What is going on if i used this? Will the device automatically select the appropriate mediaCodecs?

4

Yes, in the same order of preference as the codecs given to the Router.