need help with these question , Please explain each question in a paragraph

(1 A). A nave linear searching algorithm with negligible startup overhead takes two tenths of a second to find an item in a list of 75,000 entries. The time budget for the searching algorithm in your program is three fourths of a second. How big does the list of entries need to get before you need a better searching algorithm?

(1 B). A binary searching algorithm has logarithmic (log ) performance. It takes ten seconds to find an item in a list of 10,000 entries. Somebody decided to throw it onto a server with a moderately large database without modification, and it is now searching a list of 100,000,000,000 entries. How long do you expect it to take to find an item? How did you arrive at your answer?