php test for the applicants

<?php

// 1
// php arrays knowledge
// Here are $products array. The owner wants to increase all the prices by 15%
// please loop through the array and increase each price by 15%
//
// you may use http://phptester.net/ and print_r or var_dump to show the results

$products = [
    'mop' => [
        'quantity' => 18,
        'price' => 12,
    ],
    'hammer' => [
        'small' => [ 'quantity' => 2, 'price' => 24 ]
    ],
    'furniture' => [
        'kitchen_stuff' => [
            'chair' => [ 'quantity' => 7, 'price' => 53 ],
            'table' => [
                'small' => [ 'quantity' => 8, 'price' => 113 ],
                'large' => [ 'quantity' => 1, 'price' => 214 ]
            ]
        ],
        'sofa' => [ 'quantity' => 1, 'price' => 345 ]
    ]
];


// 2
// MYSQL knowledge
// here are 3 mysql tables
// 1. Please make a mysql query to list users, but only those who have a car
// <name> => <car name>
//
// 2. Please make a mysql query to pull out emails of only those users who have bmw model


//users
id | name | email
-------------------
1  |  John | aaa@bbb.cc
2  |  Sara | abb@bbb.cc
3  |  David| abc@bbb.cc
4  |  Nick | acc@bbb.cc
5  |  Mike | aac@bbb.cc

//users_cars
id | user_id | car_model_id
----------------------------
1  | 2       | 1
2  | 3       | 2
3  | 4       | 3
4  | 5       | 3

//car_models
id | model
----------
1  | toyota
2  | kia
3  | bmw



// 3
// HTML knowledge
// Using codepen please create a html layout of a page
// 80px - (bg yellow) header
// 200px - (bg gray) bottom pushed to the bottom of the page. Pushed but not a fixed position.
// 20% of width - (bg red) side bar
// 80% of width white main content
// no scroll bar if main content is smaller than 100% of height.
// footer should remind at the bottom but not overlay the content from main
|------------------|<-header
|__________________|
|    |             |
|    |             |
|    |             |<--main block
|    |             |
|------------------|
|   footer         |
|------------------|

// 4 (optional)
// JAVASCRIPT knowledge:
var myNumber = 12;

// please make chinable function "doubleNumber"  (a prototype function) to have these results

console.log(myNumber.doubleNumber()); //24
myNumber = 20;
console.log(myNumber.doubleNumber()); //40

// 5
// regex knowledge
// here is part of a log file. Please retrieve by using regex
// all emails that have sent us emails ( from=)
// Please test the result at https://regex101.com/
//
received from="aaa@bbb.cc.uk" via="aaabbb.ee" ip="unknown" to="qqq@ccc.uu"
received from="aab@bgb.cc" ip="11.22.33.44" to="qqq@ccc.uu"
received from="acaf@hhh.cc" ip="unknown" to="qqq@ccc.uu"
received from="ac56af@abc22.name" ip="88.55.21.56" to="qqq@ccc.uu"