add: questions for the loops section

13-loops/questions/02-randomization.md

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+## What's pseudorandom number generation?
+1. Numbers appear to be randomly generated but in reality they are not *CORRECT*
+2. Generating random numbers according to the physical laws
+3. Generating pseudo even and odd numbers
+
+> **1:** Computers are deterministic machines. They can't generate truly random numbers (unlike actual physical processes).
+
+
+## What's a seed number?
+1. Exchanging of random numbers between two computers
+2. It's used to getting a random number between 0 and the seed number
+3. It's used initialize a pseduorandom number generator *CORRECT*
+
+
+## Which package is used to generate pseudorandom numbers in Go?
+1. pseudorand
+2. rand *CORRECT*
+3. random
+4. randomizer
+
+
+## What does [0, 5) mean?
+1. A range of numbers between 0 and 5 (excluding 5) *CORRECT*
+2. A range of numbers between 0 and 5 (including 5)
+3. Just 0 and 5
+4. Just 0 and 4
+
+> **1:** Right. The square-brace means: "inclusion". The parenthesis means: "exclusion". So, [0, 5] means: 0, 1, 2, 3, 4. It's called the "mathematical interval notation".
+
+
+## Why this function call would not work?
+```go
+rand.Intn(0)
+```
+1. First you should seed it
+2. It expects two arguments
+3. Intn works within a range of [0, 0). So, it doesn't make sense to include 0 and not include 0 at the same time. *CORRECT*
+
+> **1:** That's not the cause of this error. You don't always have to seed it.
+> **2:** No, it does not.
+
+
+## What does this program print?
+Note that, each seed number below returns pseudorandom numbers as these:
+
+```
+Seed: 0
+  3 3 6 8 4 1 9 3 6 6
+
+Seed: 1
+  1 1 9 3 2 4 7 6 6 6
+
+Seed: 2
+  10 1 2 2 0 6 4 1 0 5
+```
+
+Here's the program:
+
+```go
+package main
+
+import (
+	"fmt"
+	"math/rand"
+)
+
+func main() {
+	for i := 0; i < 3; i++ {
+		rand.Seed(int64(i))
+		fmt.Print(rand.Intn(11), " ")
+		fmt.Print(rand.Intn(11), " ")
+	}
+}
+```
+1. 3 1 10 3 1 1
+2. 3 6 1 6 10 5
+3. 1 10 1 1 3 3
+4.  3 3 1 1 10 1 *CORRECT*
+
+> **4:** The numbers are determined depending on the seed number. So, this loop, seeds the pseudorandom generator with 0, 1, and 2 respectively.
+> 
+> And, after each seed, it calls Intn twice to generate two random numbers.
+> 
+> So, if you look at the result, 3 3 is the first two numbers of Seed: 0. 1 1 for Seed: 1. And, 10 1 for Seed: 2.
+
+
+## What you should do if you want the pseudorandom generator to produce random numbers each time you run your program?
+1. You need to seed it like this: rand.Seed(rand.Random)
+2. You need to seed it like this: rand.Seed(time.Now().UnixNano()) *CORRECT*
+3. You need to seed it like this: rand.Seed(time.Now())