Doug is a salesperson in a retail store and earns $75 per week, plus 15% of his weekly sales. If Doug makes $555 one week, what are his sales for that week?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

What is the volume of a cone with a height of 6 cm in the radius of 2 cm

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?