What is the perimeter of the triangle? 20mm 15mm 25mm

What is the ratio for the surface areas of rectangle prisims shown below given that they are similar and that the ratio of their edge lengths is 7: 3

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?