Question

PLEASE HELP IT'S TIMED

Answer 1

The 3rd one.....................

Answer 2

Fourth option

Explanation:

An m×n matrix is a matrix with m rows (horizontal lines) and n columns (vertical lines).

By definition, the multiplication of two matrices
`m_1`×
`n_1` and
`m_2`×
`n_2` can be done only if:

`n_1 = m_2`

In the first option:

`n_1 = 2\\m_2 = 1`

In the second option

`n_1 = 1\\m_2 = 2`

In the third option

`n_1 = 2\\m_2 = 1`

In the fourth option

`n_1 = 1\\m_2 = 1`

`n_1 = m_2` Multiplication can be done