Which of the following greatly contributes to the cause of tides?
a) earths rotation on its axis, which causes water to move
b) strong winds blowing water onto coasts
c) differences in how much the sun pulls on different part of earth
d) differences in how much the moon and the sun pull on different parts of earth

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)