### Robotic Sub To Dive Into Earth's Deepest Sinkhole

The earth's deepest sinkhole is in Mexico and it is called Zacatòn.

```   [source: CMU.edu (Robotics Institute at Carneigie Mellon University)]

"An underwater robot, shaped like a flattened orange, maneuvered
untethered and autonomously within a 115-meter-deep sinkhole during
tests this month in Mexico, a prelude to its mission to probe the
mysterious nether reaches of the world's deepest sinkhole."

[...]

"But no one knows how deep Zacatòn goes. Human divers, descendin
far below safe depths, have made it to 282 meters without reaching
bottom. Sonar doesn't work over long distances in the confines of
the cenote, and current measurements peter out at around 270 meters.
```

Autonomous operation means "independent of human control once it is under way." The robotic sub (which is named DEPTHX) has an "array of 56 sonar sensors - 32 with a range of 100 meters and 24 with a range of 200 meters - that send sonar beams out in all directions. DEPTHX uses the sonar data to detect obstacles and locate itself on a map, providing precise navigation in the pitch-black deep water."

##### Exercises
1. One meter equals `1.0936133 yard`. Human divers discovered that Zacatòn is at least `_______ yards` deep.

2. A football field had an end-line to end-line length of `91.44 meters`. No or Yes: Zacatòn has a depth of at least three football fields.

3. The average range of Zacatòn's `56 sonar sensors` is `__________ meters`.

4. `56 = 5 x 10^___ + 6 x 10^___`

5. No or Yes: `56` is the sum of six consecutive primes starting with `3` and ending with `17`.

6. No or Yes: The prime factors for `56` are `2^3` and `7`.