There are two password systems:

A$.$ Your password must be six pins. It must include characters from at least two of the following categories: numbers, capital letters,

lower$-$case letters, and special characters from $1$@#$$\%{?}^{{?}^{?}}$&$**0$

B$.$ Your password must be six pins. You can use numbers, capital letters, lower letters, and special characters from $1$@#$$\%$ $$***0$

Please answer the following questions:

What is the search space for System $B?$

From the system designer's perspective, which system is safer? Why?

From a smart user's perspective, which system is safer? Why?

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