$(1$ point$)$ In this problem we explore the relationship between password length and cryptographic

security.

Suppose a password consists of $10$ ASCII characters. You can review the ASCII characters here..

There are exactly $2^7=128$ ASCII characters; we will assume every character in the password is

ASCII $($non$-$printing characters are allowed$).$

What is the size of the keyspace that consists of passwords of this form?

What is the equivalent key length in bits?

Assuming that you could

check one password every ${10}^{-10}$ seconds, what is the worst case running time for cracking this

password by brute force search $($in days$)?$

Now assume that the user

used only $35$ characters from the keyboard. What is the key length in bits in this case?

How many days, in the worst case, would it take to break this weaker

password? You can't round to the nearest day here $--$ be as exact as possible.

Supposing you used only $35$ characters, how long is the shortest

password that achieves $137$ bits of security?