PLZ HELP DOING MY FINALSS Calculate the following:

4.0 x 10¹⁴ x 7.0 x 10¹³
(show working)

Acollection of coins has value of 64 cents. there are two more nickels than dimes and three times as many pennies as dimes in this collection. how many of each kind of coin are in the collection?

Sally deposited money into a savings account paying 4% simple interest per year.the first year,she earn $75 in interest.how much interest will she earn during the following year?

What is mean median mode and range?