In ΔLMN, l = 810 cm, m = 620 cm and ∠N=166°. Find the length of n, to the nearest centimeter.

(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 ?

Can someone me and do the problem plz so i can understand it more better

James adds two numbers a + b. sally adds the same two numbers but reverse the order b + a what property of addition assures us that james and sally will get the same sum