One us dollar is currently worth 0.79 euro (€). if you exchange $522 for euros, how many euros will you have?

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

Consider a cube that has sides of length l. now consider putting the largest sphere you can inside this cube without any point on the sphere lying outside of the cube. the volume ratio -volume of the sphere/ volume of the cube is 1. 5.2 × 10−1 2. 3.8 × 10−1 3. 1.9 4. 2.5 × 10−1 5. 3.8

Tan198=asin164=? how to solve this? ?