Express A in the form A=L1DU1 where L1 is the lower triangular with 1’s along the main diagonal, U1 is the upper triangular, and D is a diagonal matrix, given A=[(2 1 - 1) (-2 - 1 2) (2 1 0)]​

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

Barbara deposited $300 in the bank. if the bank pays her simple interest at the rate of 4 percent per year, how much money will she have in her account at the end of 9 months?

Having a hard time understanding this question (see attachment).