Iunderstand how to do ratios but efgh having no numbers is throwing me off

The deck that kenneth is building is in the shape of a parallelogram abcd the measure of angle c is one third the measure of angle b find the measure of each angle of the deck

(a) calculate the molarity of a solution that contains 0.0345 mol nh4cl in 400 ml of solution. (b) how many moles of hno3 are present in 35.0 ml of a 2.20 m solution of nitric acid? (c) how many milliliters of 1.50 m koh solution are needed to supply 0.125 mil of koh ?

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab