Please share your thoughts on these

A Project with a total funding of $100,000 finished with a BAC value of $95,000. What term can BEST describe the difference of $5,000?
1.Cost Variance
2.Management Overhead
3.Management Contingency Reserve
4.Schedule Variance

Answer 3, What is the assumption here ?

 What is the BEST way to make an accurate forecasting of ETC?
1.Manual Forecasting of cost of remaining work.
2.BAC – EV
3.(BAC – EV)/CPI
4.EAC - AC

Answer 1. My choice was 4 ,