If Ahmed's wealth was calculated at the end of the month of Dhul-Hijah as follows: Gold weighing 40 grams, gram price 50 riyals. silver coins 1000 riyals 500 dinars, the exchange rate of the dinar 10 riyals a current account with the Islamic Nation Bank of 6000 riyals shares of 1000 shares, the market value of the share 5 riyals an investment deposit with the Islamic Bank of Egypt 1500 riyals investment certificates 2000 riyals an amount in the savings book of 1000 riyals and amount of 500 riyals cash - What is the amount of zakat due by Ahmed?