You want your portfolio beta to be 1.61. Currently, your portfolio consists of $100 invested in stock A with a beta of 1.59 and $300 in stock B with a beta of 2.23. You have another $400 to invest and want to divide it between an asset with a beta of 1.66 and a risk-free asset. How much should you invest in the risk-free asset? The amount you invest in the risk-free asset could be either positive or negative. Please input the amount rounded to two decimal places (without the $ sign)