Ramona retired from the railroad after $40$ years of service at age $72$ in $2022.$ She is a widow and files as single. She received the Form RRB$-1099$ below. She received a Form RRB$-1099-$R with $$18,250$ in box $7$ and reports it on line $5$b of her Form $1040/1040-$SR$.$ She received no other taxable income. Up to $\_\_\_\_\_$ of her Tier $1$ benefits may be taxable.

$($gross paid $1$ tier one paid in $2022$ So the gross social security benefit equivalent portion is $$17,500,$ The net for social security benefit equivalent is $$17,500,$ the Medicare premium total is $$2,041)$

$0\%.$

$50\%.$

$85\%.$

$100\%.$