Tossing a number cube numbered from 1 to 6 and getting an even number that is greater than or equal to 2

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?

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?

Luisa sells stuffed animals. she sells her stuffed elephant for $34.90, and the sales tax is 6% of the sale price. about how much is the sales tax on the elephant?