a and b can do a piece of work in 12 days, b and c in 15 days and c and a in 20 days. how much time will a alone take to finish the job

15 points ! ~ see if you know the answer to both you!

Before simplifying, how many terms are there in the expression 2x - 5y + 3 + x?

Match the scale and the actual area to the area of the corresponding scale drawing. scale: 1 inch to 4 feet actual area: 128 square feet scale: 1 inch to 7 feet actual area: 147 square feet scale: 1 inch to 8 feet actual area: 256 square feet scale: 1 inch to 5 feet actual area: 225 square feet area of scale drawing scale and actual area scale drawing area: 3 square inches arrowright scale drawing area: 8 square inches arrowright scale drawing area: 4 square inches arrowright scale drawing area: 9 square inches arrowright