Please help! fill in the blank with a number to make an expression a perfect square ​

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

Mr. roseanne will buy 12 1/2 pounds beef for for a cookout. the price for the first 3 pounds of beef is $4.99 per pound. after that, the price is $4.49 per pound. how much will mr.roshan pay for the beef

Atrain is travelling from new orleans to memphis at a constant spend of 79 miles per hour. new orleans and memphis are 395.1 miles apart. how long will the train be to reach memphis round to the nearest tenth