Work out the value of (6.8x10^2) x (1.3x10^-3)

Three cylinders have a volume of 2836 cm^3. cylinder a has a height of 900 cm. cylinder b has a height of 225 cm. cylinder c has a height of 100 cm. find the radius of each cylinder. use 3.14 as an approximate for π

Use the graph of the sine function y=2sinθ shown below

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?