Can anyone help with these, I am having big problems understanding annual, present, and future values.

Q3) The Highway Department expects the cost of maintenance for a piece of heavy construction equipment to be $5,000 in year 1, then increase to be $5,500 in year 2, and to increase annually by $500 through year 10. At interest rate of 10% per year determine the present worth of 10 years of maintenance costs.

Q4) Ryan Borrowed $15,000 now with a 7% interest rate compounded annually. He needs to pay them back over 7 years starting from the end of the first year, what will be Ryan's annuity assuming that he will miss the 4^th payment

Q5) Engineering company just purchased a new CAD software for $8,000 now and annual payments of $500 per year for 6 years starting 2 years from now for annual upgrades. What is the present worth of the payments if the interest rate is 6% per year?