Write a subtract to compare problem and draw a bar model to solve it

Ineed with number 6 , explain how to get 1978

Study results indicate that the mean length of time people spend on a bus in a city is between 21.2 min and 24.5 min what is the study margin of the error?

Alex buys a home for $276,400. his home is predicted to increase in value 3.5% each year. what is the predicted value of alex’s home in 25 years? a. 621,357 b. 635,191 c. 653,201 d. 673,415