Jack bought an external hard drive with 1 TB, or 1x102, bytes of available space. So far he has used up 7.4x108 bytes. How much space does he have available?

What is the number 321,000,000 in scientific notation? also what is the number? ?

Diane’s bank is offering 5% interest, compounded monthly. if diane invests $10,500 and wants $20,000 when she withdrawals, how long should she keep her money in for? round to the nearest tenth of a year.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?