Starterware/MSP430FR6972: how to calculate ADC12_B sample frequency exactly

Part Number:MSP430FR6972

Tool/software: Starterware

Hi Sir，

I want to know how to calculate ADC12_B sample frequency exactly. From the page 673 of MSP430FR6972 User's Guide , I knew that the ADC sample period  is composed by  sample time， sync time ，convert time and one clock cycle. The picture is following :

But ,I have some doubts:

1. how long does the sync time?

2.what's the means of ADC local reference buffer ?  Is the reference voltage generated by REF_A module a ADC local reference buffer?

3.what clock is the one clock cycle 's  clock source， MCLK or ADC12_B clock?

Regrads,

Jent