Good day everyone. I am greatly excited making my Acheivement 2 Post which is geared towards understanding Basic Security on steem.
The importance of having a seem wallet cannot be downscored, hence, the need for us to take security measures of our accounts seriously.

QUESTION 1 :

Yes, I did that. I retrieved all my keys upon registration. The keys are Master Key, Active Key, Memo key and Posting key.

QUESTION 2 :

There are 4 Keys and each of this keys have disparities in functions .
I will explain them one by one.

ACTIVE KEY : This key is very sensitive because, It was designed for sensitive transactions such as Power Up/down, transferring funds, converting seems, updating profile details and placing a market order.

Master Key : This key is otherwise called Owner Key. It is regarded as the most powerful key on steem because , It is used for restoring and recovering any adulterated account.
It has peculiar restrictions and of such, can't be used for daily logins.

Posting Key : This key allows assess for account login, Post, up vote, down vote, edit and comments on a post. Although, this key also has restrictions and of such, cannot be used to assess account token .

Memo Key : Memo key has several functions, however, one of its vital functions is to encrypt and decrypt messages during transfer of funds.
Memo key also has restrictions and of such, can't be used for daily logins, and assess to Wallets.

QUESTION 3 :

Due to the importance of the Master password, I planned saving it in my Gmail and personal drive account. So that even If my phone or laptop device is lost, I can still have assess to it.

QUESTION 4 :

Yes, I fully understood the Lessons so well. Below are the pictures of my account to back up my answers.

Step 1 : Login to steemit using your username and posting key .

Step 2 : Click on the down arrow button symbol beside your streem balance.

Step 3 : Click "transfer" and then, enter the recipient username in the first open box and the amount of steem to be transferred in the second box.

Step 4 : Ensure all entities and parameters are correct and click on "next"

Note : Don't fail to enter active key in other to compete your transaction.

QUESTION 5 :

Yes I did. Below are the consecutive steps .

Step 1 : Login to your steem account using your username and posting key, then click on "wallet".

Step 2: Click on the down arrow symbol button and select "Power Up" .

Step 3: Insert the amount you want to Power up and afterwards, click on the Power up button.

Note : Don't fail to enter your active key in other to complete the transaction.

Now, with all of this explanations, I strongly believe I have successfully completed my achievement 2 post which has helped me fully understood the importance of Security on the platform. A million thanks to @focus now for his massive support.