How many times larger is 9 x 10^-8 than 3 x 10^-12?

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?

The length of an intercepted arc of a central angle of a circle is 4 cm. if the radius of the circle is 5 cm what is the measurement of the central angle to the nearest whole degree

Layla answer 21 of the 25 questions on his history test correctly. what decimal represents the fraction of problem he answer incorrectly.