Don't just guess if you don't know. i need the exact answer

What’s the domain of this function? fastttt

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?

The equation of line wx is y=2x-5. write an equation of a line perpendicular to line wx in slopeintercept form the contains points (-1,-2)