Prove that it is impossible to have $4.50 in dimes and quarters with the number of quarters being twice the number of dimes

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?

Pls yall i really need the answer fr fr

Find the rate of change for the situation.you run 7 miles in one hour and 21 miles in three hours.