(2-3i)*(3+4i) perform following operations

Me. drysdale earned 906.25 in interest in one year on money that he had deposited in his local bank if the bank paid an interest rate of 6.25% how much money did mr. drysdale deposit

Acompany wants to reduce the dimensions of its logo by one fourth to use on business cards. if the area of the original logo is 4 square inches, what is the area of the logo that will be used on the business cards?

Acertain volume of water contains 100000 hydrogen atoms and 50,000 oxygen atoms how many hydrogen atoms are in a volume of water containing 4 million oxygen atoms