What is the definition of a plane?

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

From the beginning of the day the temperature rose 15 degrees so that by 4 pm it was 87 degrees. what was the temperature at the start of the day

The amount cami raised during last year’s charity walk, $45.50, is 7/10 of the amount she raised this year. which equation represents n, the number of dollars she raised this year?