Subject: how market would valuate BRK
It's not unreasonable that the market would valuate BRK as follows:

Operating business worth 15 x operating earnings = 15 x $18*2 billions = $540 billions
Investments in equity securities = $353 billions
Cash = $150 billions

total between: 540+353+100=$993 to 540+353+150= $1043 billions

that's 25% to 31% higher than today's price.