WIll mark Brainliest Question is in attachment

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

Which ordered pair is a solution to the system of linear equations? 2x + 3y= 6 –3x + 5y = 10

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?